1. Honeywell Thermostat Instructions Chronotherm

• POST a QUESTION or READ FAQs about Room Thermostats for Air Conditioners & Heating Systems or heat pumps: thermostat operation, wiring, adjustment & repair procedures

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Heating & Cooling Thermostats, how to install, set, troubleshoot & repair home page: this article series explains selection, installation, use, setting, and adjustment of heating or cooling system room thermostats or 'wall thermostats'.

Here in the article links found at the ARTICLE INDEX the bottom of this article and at the top of this article we provide a complete guide to buying, installing, using, adjusting, & repairing thermostats for heating or air conditioning or heat pump systems.

This article series answers most questions about central heating system troubleshooting, inspection, diagnosis, and repairs. Our page top photograph illustrates an antique room thermostat still in use at the Franklin Delano Roosevelt FDR Estate in Hyde Park, NY.

We also provide a MASTER INDEX to this topic, or you can try the page top or bottom SEARCH BOX as a quick way to find information you need.

Types of Thermostats Used to Control Air Conditioning & Heating Systems

Discussed here: Heating & Air Conditioning Thermostats where are thermostats usually located, what types of thermostatic controls are used onvarious heating and cooling systems, how do we find all of the thermostats, how do we set, adjust, and use thermostats

In this photograph we illustrate a traditional Honeywell round bimetallic-spring type room thermostat that was used in thousands if not millions of homes in North America & other countries. The interior of this traditional thermostat can be seen at HEAT ANTICIPATOR ADJUSTMENT.

If your heating system is not working at all, start at HEAT WON'T TURN ON.

Article Series Contents:

• THERMOSTATS, HEATING / COOLING
  • NEST LEARNING THERMOSTATS - home
    • NEST THERMOSTAT WIRING INSTRUCTIONS for use with their Energy Kinetics 2000 MANAGER [PDF]
• THERMOSTAT SETTING INSTRUCTIONS - Separate article - How to Set the Thermostat
• THERMOSTAT OPERATION - how digital thermostats & their displays work
• THERMOSTAT TROUBLESHOOTING - Separate article: What to check if a thermostat is just not working
  • THERMOSTAT ERROR CODES - How to Translate the error codes on digital thermostats
• THERMOSTAT WIRE CONNECTIONS - how to wire up all types and brands of heating & cooling thermostats
• LINE VOLTAGE THERMOSTATS for Electric Heaters & Electric Baseboard Heat

Traditional & Early Clock Thermostats & How They are Set

The round Honeywell® wall thermostat shown in the photo above has been locked in a plastic enclosure to prevent people from changing its set temperature.

Set temperature and how the thermostat works are described in excruciating detail below for each of the different types of room thermostats.

At HEAT ANTICIPATOR ADJUSTMENT we describe how an internal adjustment can be made to this thermostat to improve its operation in some types of heating systems.

Also see THERMOSTAT CALIBRATION where we discuss the accuracy and calibration of room thermostats.

The Historic GE Technotron & Honeywell Chronotherm Thermostats

Our photo illustrates General Electric's Telechron thermal control (room thermostat) first produced in 1933.

This was probably the first clock-controlled automatic set-back residential wall thermostat produced in the U.S. The top of the thermostat is hinged to permit acces to its interior for wiring.

GE Telechron Thermal Control (thermostat) is described by the U.S. Smithsonian Institute's National Museum of American History:

General Electric manufactured this Thermal Control thermostat around 1933. The thermostat came equipped with a Telechron synchronous motor that powered the clock attached to the thermostat.

The clock allowed the furnace to turn on and off at a certain time, and the thermostat has two wheels on the right and the left, which allowed the home owner to set a desired temperature during the day and during the evening. - retrieved 2017/12/31,

- original source: Smithsonian Institute, National Museum of American History, Constitution Avenue, NW Between 12th and 14th Streets Washington, D.C., USA, americanhistory.si.edu/collections/search/object/nmah_1392737

Below is a later clock-thermostat more-widely sold in the U.S, the Honeywell Chronotherm wall thermostat, another clock-operated automatic day-night room thermostat.

The Honeywell Chronotherm thermostat is described in this 1950's HONEYWELL THERMOSTAT GUIDE [PDF] produced by the Minneapolis-Honeywell Regulator Company, Minneapolis 8, Minnesota, (1950) reproduced from a Dodge building products catalog. Clicking on the first page in that PDF file should return to this web article.

Excerpts from the original Honeywell Chronotherm product literature:

The Chronotherm is an electric clock thermostat which automatically matches the room temperature to your living schedule. All day long it controls the burner to maintain the exact temperature you want.

A special 'Comfort' feature in the instrument assures extremely accurate control. It senses heat requirements quickly. There is no under-heating to cause chills, no overheating to waste fuel.

At bedtime, this never-forgetting instrument lowers the room temperature as you wish for your sleeping comfort. ... it saes up to 20% of yoru costly fuel.

Then in the morning the Chronotherm automaticallyi raises the room temperature to the daytime cofort level. ...

If you plan to leave over a week-end, it's a simple matter to save fuel while you are gone.

The handy finger-tip levers on the Chronotherm allow you to lower the temperature settings as you wish. - 1950's HONEYWELL THERMOSTAT GUIDE

Two other Honeywell thermostats sold in 1950 were the Time-O-Stat for semi-automatic day-night temperature control, and the Acratherm thermostat. We illustrate both of these below.

Room thermostats for air conditioning work and are set the same as when these devices are used for controlling heating systems. We provide lots of detail about how these devices work - see THERMOSTAT SETTING INSTRUCTIONS.

Traditional Rectangular Wall Thermostats and how they are set

On this wall thermostat the red pointer shows the current room temperature.

The black pointer at the center of the scale at the bottom of the little window shows the temperature that the thermostat has been 'set' to.

The 'Set Temperature' is the temperature that the room occupant is requesting.

Moving the thermostat adjustment lever (located at the top, side, or bottom of the thermostat depending on the model) will change the set temperature up or down, causing the heating or air conditioning system to turn on or off as needed.

SeeTHERMOSTAT SETTING INSTRUCTIONS.

Programmable, Digital Room Thermostats & How They are Set

Digital room thermostats are illustrated in our two photographs shown here. A modern digital thermostat uses an LCD type display to show the current room temperature along with other information.

Typically the display changes in response to pushing the thermostat control buttons.

Most digital room thermostats are 'programmable' - you can set the thermostat to set back the room temperature at night (in heating mode, for example) and many models allow different time and temperature settings both throughout the day and for individual days of the week as well.

Our digital thermostat shown at left indicates the time (5:43 PM) in the left side of the display and the current temperature (53 °F) in the right side of the display.

With the thermostat's plastic cover 'shut' it's operation is very simple, just showing up and down arrows that temporarily call for a higher or lower room 'set' or 'desired' temperature.

We opened the plastic thermostat cover to show additional detailed controls and instructions.

Our Favorite Room Thermostat - The Honeywell RTH2300 / RTH221

The Honeywell RTH2300 / RTH221 series room thermostats are easy to program, permit different weekday and weekend programs, and include a 'hold' button that is invaluable for keeping the thermostat at a fixed setting without losing the whole program.

Honeywell displays a 'Rated Overall Best Brand' sticker on the packaging indicating that this model received a 'Best' rating by an independent Frost & Sullivan study.

At THERMOSTAT SWITCHES, INTERNAL we describe how to set this thermostat's internal 'Gas' or 'Oil' slide switch.

At TROUBLESHOOT ACCURACY & RESPONSE of THERMOSTATS we describe the accuracy of this thermostat, typically +/- 1° F.

We describe the operation of a typical digital room thermostat for heating or air conditioning later in this article at DIGITAL ROOM THERMOSTAT OPERATION

A simpler programmable Honeywell® digital room thermostat is show in our photo at left. This is a Honeywell CT2700 Electronic Round Programmable Thermostat.

The thermostat is showing the current time (12:15 PM) and current room temperature (67 °F).

This unit does not provide additional buttons under a cover. But by pressing the center 'Set' button the display changes to allow the user to set a desired time and temperature setting for day and night time temperatures.

At THERMOSTAT SWITCHES, INTERNAL we discuss setting the thermostat's internal F/E toggle switch.

Watch out: we installed and tested two of these thermostats over several years of use. While the device is simple, un intimidating, and easy to program, the lack of a 'hold' feature was annoying and required more fooling around; we also would have liked an additional daytime automatic setback period that this device doesn't offer.

But the worst discovery was that our oil burner was short cycling, sometimes turning on for just a few seconds - a problem that we finally traced to a defect in one of these thermostats. (The problem ceased when we swapped in our preferred thermostat shown above). We also found the flat cable wiring of this thermostat very fragile - eventually the display cable simply detached itself from its contacts.

The Nest™ Learning Thermostat - home automation features include buiding occupancy monitoring & communicating with the Nest Protect Carbon Monoxide & Smoke Detector

'The Nest Learning Thermostat' is an electronic device that can control room temperatures and possibly other components connected to or installed as part of a home automation system. We have installed three of these in our test building and will report further on ease of installation, programming, and use as well as using and adjusting the Nest thermostat remotely from your cellphone, computer, or tablet.

Photo: the Nest® Learning Thermostat on demonstration display at a Home Depot store in 2013. [Click to enlarge any image]

Nest Learning Thermostat Installation & Use Article Series

• NEST LEARNING THERMOSTATS - home
  • NEST THERMOSTAT WIRING INSTRUCTIONS for use with their Energy Kinetics 2000 MANAGER [PDF]

Radiator Thermostats & Baseboard Thermostats, Automatic - TRVs & How They are Set

Several manufacturers provide thermostatically-controlled radiator valves (Armstrong, Danfoss, Hoffman Specialty, Jacobus (Maid'O'Mist) and others).

Automatic radiator/baseboard valves provide thermostatic controls that can be installed on individual hot water radiators, steam radiators, or heating baseboards. The automatic radiator or baseboard valve will automagically open or close to attempt to control room temperature to the desired level.

Shown at left is an adjustable individual thermostatic control installed on a hot water radiator in Molde, Norway.

For details see RADIATOR VALVES & HEAT CONTROLS This article describes these automatic or thermostatically controlled radiator valves (such as the Armstrong RV-4) that will allow you to set the desired room temperature.

Also see RADIATOR STEAM VENTS, 1-PIPE SYSTEMS for a description of automatic steam vents used to control the rate at which steam heat radiators will get hot. Automatic steam vents can help balance the delivery of otherwise uneven steam heat throughout a building.

Remote Control Room Thermostats for Heating and Air Conditioning & How to Use Them

Remote control thermostats such as the unit shown at left are usually used with air conditioning or heating split systems using an outside compressor/condenser unit and one or more indoor wall-mounted cooling or heating units..

The thermostat controls in the hand-held remote control communicates with a wall-mounted air conditioner or heater using infra red signals.

The open finned area at the bottom of this Sanyo control (at the left in our photo) permits ambient air to enter the control for purpose of sensing the air temperature.

A control such as this Sanyo™ unit can be quite sophisticated and include automatic set back temperatures, timers, etc.

See SPLIT SYSTEM AIR CONDITIONERS & HEAT PUMPS for details, including troubleshooting and fixing remote control thermostats themselves

as we describe in detail at SPLIT SYSTEM AIR CONDITIONERS & HEAT PUMPS-FAQs

Hand held A/C remote control does not seem to be working

Have a hand held remote for TCL air-conditioner (split model TAC-30CHS/G). when we set temperature, conditioner blinks what you want it to be, then it goes to inside temperature (suppose to do this) but then it quickly jumps to 34 degrees & switches off. Guessing it is thermostat? Anne Webber 9/2/11

Reply:

Anne, sounds odd to me too. Try

• putting a new battery in the hand held remote and reinitializing it
• turn off all system power when you're not already in the middle of a cooling cycle and leave it off for a minute - or if you were in cooling cycle, wait an hour, then turn power back on - resetting everything.
• be sure you've got clear line of sight between the remote A/C controller and the receiving unit
• be sure that the wall mounted thermostat (if there is a separate one) is properly located where it can see or communicate with the indoor wall mounted blower assembly.

If those steps don't fix the problem and you don't see more help in the installation and use manual, it's time to ask for an HVACR service call as there could be a bad controller, thermostat, or control board.

Outdoor Thermostats on the Heat Pump Compressor-Condenser Unit

Heat Pump Outdoor Thermostats are used to control the turning on and off of backup heat.

Our photo (left, courtesy of Neal Renn shows the thermostatic control unit in the outdoor compressor/condenser unit of a residential heat pump.

See HEAT PUMP THERMOSTAT, OUTDOOR and BACKUP HEAT for HEAT PUMPS

Also see Detailed Case of a Heat Pump that Put out Heat when Cooling was Required

Choices of Room Thermostat Models, Brands, Features

In the article above and at Related Links (near page top) we describe the installation and use of most types of room thermostats used for heating, cooling, even dehumidification in buildings. But there are hundreds of models and features available.

The largest selection of room thermostats we find anywhere is at Grainger who has over 250 models in their online catalog. http://www.grainger.com - but beware not every thermostat description necessarily names all features.

Room Thermostat Temperature Sensor Mechanisms

Our photograph illutrates a traditional bimetallic spring used in many thermostat interiors to sense and respond to room temperature.

A variety of methods are used to sense room temperature and to communicate that data to the thermostat's heating or cooling switching mechanism:

Bimetallic Element thermostats use a bimetallic spring consisting of strips of two different metals fused together, typically into a coil shape. As room air temperature causes the two metals to expand or contract at different rates, the effect is that the spring coils up or un-coils, moving a switch that turns heating or cooling or or off.

Bellows Element thermostats are filled with a volatile liquid that vaporizes at temperatures typically found indoors. As the liquid vaporizes pressure inside the bellows expands, translating temperature change into the movement of a contact to turn heating or cooling on or off in response to building temperature.

Thermistor-type thermostats use a tiny solid-state electronic component, a type of resistor whose electrical resistance changes in response to temperature. By combining the thermistor with appropriate additional circuits and controls the thermostat uses the change in resistance to control the switching of the thermostat's control of cooling or heating on or off in response to room temperature.

For details: at TEMPERATURE RESPONSE of ROOM THERMOSTATS we give a detailed description of how room thermostats sense & respond to room temperature, and

at HEAT ANTICIPATOR ADJUSTMENT

and THERMOSTAT SWITCHES, INTERNAL we explain methods used to fine-tune thermostat operation in response to temperature swings, thus adjusting the burner on-cycle or fan operation if the heating system uses a fan.

Also see THERMOSTAT CALIBRATION where we discuss the accuracy and calibration of room thermostats.

Steam Heat Room Thermostats, Wall-Mounted

Room thermostats used to control steam heat may vary from their cousins illustrated above, or not - depending on just what the thermostat is controlling. In a residential application a standard room thermostat works fine to turn on or off the steam boiler.

But in larger buildings you may find that the room thermostat for steam heat is controlling a valve or relay that admits steam to radiators in one room or in just one section of a building.

In our photo at left, this wall thermostat controls steam heat in a college office in Poughkeepsie, NY.

[Click to enlarge any image]

The upper scale indicates the current room temperature.

The lower dial-scale is the set-temperature adjustment on this thermostat. The thermostat controls a steam radiator valve that in turn admits or shuts off heat into the space managed by this device.

RADIATOR & BASEBOARD THERMOSTATS, Automatic - TRVs provide an alternative that can control individual hot water or steam radiators in buildings.

Thermostat Accuracy: Settings vs Room Temperature

Reader Question: Honeywell RTH 2300 thermostat in cool mode accuracy

13 Aug 2015 Bryan said:

Office environment with a HONEYWELL RTH2300 thermostat . . . in Cool mode Fan On and set to 75F Hold . . . cooling does not click on until 77F reached on display temp . . . and does not click off until 73F reached on display temp . . . I would think cooling should click on when above 75F . . . ie at 76F . . . and click off when below 75F . . . ie at 74F . . . is this operating within standard tolerance? . . .

is the thermostat defective? . . . is there any means to rectify to hold at 75F?

Right now there is a 4 degree variance which at 77F is slightly too warm and at 73F is slightly too cool . . . would be better clicking on at 76F and off at 74F.

Thought about changing the batteries but don’t think that should have any effect as cooling is clicking on and off OK and display reading OK just at higher and lower temps than the setting.
Any comments or suggestions to rectify would be greatly appreciated.
Thanks, Bryan

Reply:

Good question, Bryan. I like the Honeywell RTH 2300 thermostat series an have installed a number of them without having the trouble you describe.

I'd expect the thermostat to respond just as you do. And I'm doubtful that batteries are the problem.

Looking at Honeywells' FAQs for the RTH2300 the company says that the thermostat accuracy is +/- 1 degree Farenheit

Your thermostat is designed to control temperature to +/- 1 F.

How often your heat turns on and off depends on may factors including the type of heating system you have, as well as how much your system needs to run to maintain your temperature setting (in other words, how cool or cold it is outside). A typical forced air system will cycle about five times in an hour (5CPH), this is normal. A typical hot water system would cycle less then that.

See TEMPERATURE RESPONSE of ROOM THERMOSTATS for details.

A Guide to Using Wall-Mounted Room Thermostats - How to Set the Thermostat

This topic has been moved to its own article now found at THERMOSTAT SET PROCEDURE

How to Set a Room Thermostat To the Desired Temperature

See THERMOSTAT SET to DESIRED TEMPERATURE

How a Digital Room Thermostat Works

See HOW DIGITAL THERMOSTATS WORK

Backup Batteries & Default Programs for Digital Room Thermostats: blank thermostat display problems

Some programmable digital room thermostats include an internal battery that will allow the device to remember the program that you have set even if there has been a power outage. This topic has been moved to its own article at THERMOSTAT BACKUP BATTERIES - for temporary or full time operation.

Heating & Cooling Control Thermostat Troubleshooting Guide

We have moved and expanded this discussion to a separate article found at THERMOSTAT DIAGNOSTIC GUIDE - link given just below.

Question: Honeywell RTH2300 thermostat not responding properly to room temperature

12 August 2015 Bryan said:
Office environment with a HONEYWELL RTH2300 thermostat . . . in Cool mode Fan On and set to 75F Hold . . . cooling does not click on until 77F reached on display temp . . . and does not click off until 73F reached on display temp . . . I would think cooling should click on when above 75F . . . ie at 76F . . . and click off when below 75F . . . ie at 74F . . . is this operating within standard tolerance? . . . is the thermostat defective? . . . is there any means to rectify to hold at 75F?
Right now there is a 4 degree variance which at 77F is slightly too warm and at 73F is slightly too cool . . . would be better clicking on at 76F and off at 74F.
Thought about changing the batteries but don’t think that should have any effect as cooling is clicking on and off OK and display reading OK just at higher and lower temps than the setting.
Any comments or suggestions to rectify would be greatly appreciated.
Thanks,

Reply: check for dirt, dust, or drafts before replacing a non-responsive thermostat

Good question, Bryan. I like the Honeywell RTH 2300 thermostat series an have installed a number of them without having the trouble you describe.

I'd expect the thermostat to respond just as you do. And I'm doubtful that batteries are the problem.

1. FIRST: inspect the thermostat closely to be sure that no clod of dust or crud is blocking the little thermistor that senses temperature.
2. SECOND: check that the thermostat is not being confused by external conditions such as location on a wall that exposes the thermostat to hotter or cooler temperatures than the actual room temp. A subtle example can be a convection current running through an uninsulated interior wall cavity that is blowing cool air into the thermostat from its back-side through the wiring opening in the wall. This is probably not your problem since if the thermostat were being thrown off by sunlight, wall mounting location, or drafts, I'd expect its room temperature to reflect that influence. You'd see instead a gap between the room temperature shown by the thermostat's indicator and an independent measurement of room temperature say in the middle of the room.

A programmed setting can also confuse us about how the thermostat should be responding if a thermostat is running under a program whose settings are not what we thought.

But if you've got the thermostat in HOLD mode then it ought to respond to temperature changes around the hold temperature setting. Double check that you see the word 'HOLD' in the display.

This Honeywell RTH2300 thermostat has some self-diagnosing circuitry which I summarize:

• It will display low battery ('Lo Batt') for 60 days before the battery is dead.
• HI: the ambient temp is above 120F
• LO: the ambient temp is below 32F - these are the operating limits of the device
• E1 or E2 = bad sensor, replace the thermostat

I'd give the company a call to ask about the response you're experiencing:

Call Honeywell Customer Care toll-free at 1-800-468-1502 or see the company's consumer website at DIYthermostats.honeywell.com.

Also see THERMOSTAT CALIBRATION where we discuss the accuracy and calibration of room thermostats.

...

Continue reading at THERMOSTAT DIAGNOSTIC GUIDE or select a topic from closely-related articles below, or see our complete INDEX to RELATED ARTICLES below.

Or see THERMOSTATS, DIAGNOSTIC FAQs

MANUALS & PARTS GUIDES - HVAC - home

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THERMOSTATS, HEATING / COOLING at InspectApedia.com - online encyclopedia of building & environmental inspection, testing, diagnosis, repair, & problem prevention advice.

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Technical Reviewers & References

• [1] Proliphix Corporate Headquarters, 3 LAN Drive Suite #100, Westford, MA 01886 Phone: +1.978.692.3375 Toll Free (U.S.): 866-IP-LIVING (866.475.4846) Fax: +1.978.692.3378 - Sales: sales@proliphix.com Marketing: marketing@proliphix.com Customer support: support@proliphix.com http://www.proliphix.com/ - quoting from the company's website:
  All Proliphix Network Thermostats come with our free Uniphy Remote Management Service. This unique offering lets you monitor and control your HVAC systems by simply pointing your Browser to our secure Proliphix Web Site. Enjoy the convenience of programming a thermostat from any location, using a simple graphical interface. No computer equipment or software is required. And since Proliphix takes care of the network configuration for you, you’ll be up and running in no time. We’ll even proactively monitor your thermostats and send you an immediate email or SMS message when an HVAC problem is detected.
• [2] 'The Nest Learning Thermostat', Nest Thermostat, 900 Hansen WayPalo Alto, CA 94304, Tel: 855-4MY-NEST, Email: info@nest.com, website http://www.nest.com/, retrieved 1/24/2013.
• [3] Honeywell Controls, the company wants you to use their contact form at this web page: http://www51.honeywell.com/honeywell/contact-support/contact-us.html
  Honeywell Consumer Products, 39 Old Ridgebury Road Danbury, CT 06810-5110 - (203) 830-7800
  World Headquarters, Honeywell International Inc., 101 Columbia Road, Morristown, NJ 07962, Phone: (973) 455-2000, Fax: (973) 455-4807 1-800-328-5111
• [3a] Honeywell Tradeline T87T Universal Thermostat Installation Instructions for the Trained Service Technician', Honeywell International Inc. Honeywell Limited—Honeywell Limitée1985 Douglas Drive North 35 Dynamic DriveGolden Valley, MN 55422 Scarborough, Ontario M1V 4Z9, 60-0830—4 G.H. Rev. 8-02, retrieved 12/1/2013 Website: www.honeywell.com
• [4] White Rodgers Thermostats and HVAC controls,
  Homeowner information: http://www.emersonclimate.com/en-US/brands/white_rodgers/Pages/wr-homeowner-info.aspx
  Contractor information: http://www.emersonclimate.com/en-US/brands/white_rodgers/wr_contractor_info/Pages/white-rodgers-contractor-info.aspx
  White Rodgers Product Catalog (don't misspell the company's name as White Rogers Thermostats) -
  http://www.emersonclimate.com/Documents/thermostats.pdf - Thermostat Catalog
• [5] Domestic Central Heating Wiring Systems and Controls, 2d Ed., Raymond Ward, Newnes, ISBN-10: 0750664363, ISBN-13: 978-0750664363, Quoting from Amazon.com:
  This unique A-Z guide to central heating wiring systems provides a comprehensive reference manual for hundreds of items of heating and control equipment, making it an indispensable handbook for electricians and installers across the country. The book provides comprehensive coverage of wiring and technical specifications, and now includes increased coverage of combination boilers, recently developed control features and SEDBUK (Seasonal Efficiency of Domestic Boilers in the UK) boilers ratings, where known.
  In addition to providing concise details of nearly 500 different boilers fuelled by electric, gas, oil and solid fuel, and over 400 programmers and time switches, this invaluable resource also features numerous easy-to-understand wiring diagrams with notes on all definitive systems. Brief component descriptions are provided, along with updated contact and website details for most major manufacturers.
• [6] 'Automatic Oil Burner Controls - Thermostats', Domestic and Commercial Oil Burners, 3rd Ed., Charles H. Burkhardt, McGraw Hill, 1969 (and later editions), ASIN B0000EG4Y8
• Hunter Fan2500 Frisco Ave.Memphis, TN 38114888-830-1326www.hunterfan.com
• [7] Fuel Oil & Oil Heating Magazine, 3621 Hill Rd., Parsippany, NJ 07054, 973-331-9545
• [8] Domestic and Commercial Oil Burners, Charles H. Burkhardt, McGraw Hill Book Company, New York 3rd Ed 1969.
• [9] National Fuel Gas Code (Z223.1) $16.00 and National Fuel Gas Code Handbook (Z223.2) $47.00 American Gas Association (A.G.A.), 1515 Wilson Boulevard, Arlington, VA 22209 also available from National Fire Protection Association, Batterymarch Park, Quincy, MA 02269. Fundamentals of Gas Appliance Venting and Ventilation, 1985, American Gas Association Laboratories, Engineering Services Department. American Gas Association, 1515 Wilson Boulevard, Arlington, VA 22209. Catalog #XHO585. Reprinted 1989.
• [10] The Steam Book, 1984, Training and Education Department, Fluid Handling Division, ITT [probably out of print, possibly available from several home inspection supply companies] Fuel Oil and Oil Heat Magazine, October 1990, offers an update,
• [11] Principles of Steam Heating, $13.25 includes postage. Fuel oil & Oil Heat Magazine, 389 Passaic Ave., Fairfield, NJ 07004.
• [12] The Lost Art of Steam Heating, Dan Holohan, 516-579-3046 FAX
• Principles of Steam Heating, Dan Holohan, technical editor of Fuel Oil and Oil Heat magazine, 389 Passaic Ave., Fairfield, NJ 07004 ($12.+1.25 postage/handling).
• [13] 'Residential Steam Heating Systems', Instructional Technologies Institute, Inc., 145 'D' Grassy Plain St., Bethel, CT 06801 800/227-1663 [home inspection training material] 1987
• [14] 'Residential Hydronic (circulating hot water) Heating Systems', Instructional Technologies Institute, Inc., 145 'D' Grassy Plain St., Bethel, CT 06801 800/227-1663 [home inspection training material] 1987
• [15] 'Warm Air Heating Systems'. Instructional Technologies Institute, Inc., 145 'D' Grassy Plain St., Bethel, CT 06801 800/227-1663 [home inspection training material] 1987
• [16] Heating, Ventilating, and Air Conditioning Volume I, Heating Fundamentals,
• [17] Boilers, Boiler Conversions, James E. Brumbaugh, ISBN 0-672-23389-4 (v. 1) Volume II, Oil, Gas, and Coal Burners, Controls, Ducts, Piping, Valves, James E. Brumbaugh, ISBN 0-672-23390-7 (v. 2) Volume III, Radiant Heating, Water Heaters, Ventilation, Air Conditioning, Heat Pumps, Air Cleaners, James E. Brumbaugh, ISBN 0-672-23383-5 (v. 3) or ISBN 0-672-23380-0 (set) Special Sales Director, Macmillan Publishing Co., 866 Third Ave., New York, NY 10022. Macmillan Publishing Co., NY
• [18] Installation Guide for Residential Hydronic Heating Systems
• [19] Installation Guide #200, The Hydronics Institute, 35 Russo Place, Berkeley Heights, NJ 07922
• [20] The ABC's of Retention Head Oil Burners, National Association of Oil Heat Service Managers, TM 115, National Old Timers' Association of the Energy Industry, PO Box 168, Mineola, NY 11501. (Excellent tips on spotting problems on oil-fired heating equipment. Booklet.)
• [21] Trane TCONT800 Series Touch Screen Programmable Comfort Control Ownes Guide, American Standard, Inc., Troup Highway, Tyler TX 75711, January 2005, Telephone: Customer Service: 1-877-3381, website: www.trane.com

Books & Articles on Building & Environmental Inspection, Testing, Diagnosis, & Repair

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Heating & Cooling Thermostats, how to install, set, troubleshoot & repair home page: this article series explains selection, installation, use, setting, and adjustment of heating or cooling system room thermostats or 'wall thermostats'.

Here in the article links found at the ARTICLE INDEX the bottom of this article and at the top of this article we provide a complete guide to buying, installing, using, adjusting, & repairing thermostats for heating or air conditioning or heat pump systems.

This article series answers most questions about central heating system troubleshooting, inspection, diagnosis, and repairs. Our page top photograph illustrates an antique room thermostat still in use at the Franklin Delano Roosevelt FDR Estate in Hyde Park, NY.

We also provide a MASTER INDEX to this topic, or you can try the page top or bottom SEARCH BOX as a quick way to find information you need.

Types of Thermostats Used to Control Air Conditioning & Heating Systems

Discussed here: Heating & Air Conditioning Thermostats where are thermostats usually located, what types of thermostatic controls are used onvarious heating and cooling systems, how do we find all of the thermostats, how do we set, adjust, and use thermostats

In this photograph we illustrate a traditional Honeywell round bimetallic-spring type room thermostat that was used in thousands if not millions of homes in North America & other countries. The interior of this traditional thermostat can be seen at HEAT ANTICIPATOR ADJUSTMENT.

If your heating system is not working at all, start at HEAT WON'T TURN ON.

Article Series Contents:

• THERMOSTATS, HEATING / COOLING
  • NEST LEARNING THERMOSTATS - home
    • NEST THERMOSTAT WIRING INSTRUCTIONS for use with their Energy Kinetics 2000 MANAGER [PDF]
• THERMOSTAT SETTING INSTRUCTIONS - Separate article - How to Set the Thermostat
• THERMOSTAT OPERATION - how digital thermostats & their displays work
• THERMOSTAT TROUBLESHOOTING - Separate article: What to check if a thermostat is just not working
  • THERMOSTAT ERROR CODES - How to Translate the error codes on digital thermostats
• THERMOSTAT WIRE CONNECTIONS - how to wire up all types and brands of heating & cooling thermostats
• LINE VOLTAGE THERMOSTATS for Electric Heaters & Electric Baseboard Heat

Traditional & Early Clock Thermostats & How They are Set

The round Honeywell® wall thermostat shown in the photo above has been locked in a plastic enclosure to prevent people from changing its set temperature.

Set temperature and how the thermostat works are described in excruciating detail below for each of the different types of room thermostats.

At HEAT ANTICIPATOR ADJUSTMENT we describe how an internal adjustment can be made to this thermostat to improve its operation in some types of heating systems.

Also see THERMOSTAT CALIBRATION where we discuss the accuracy and calibration of room thermostats.

The Historic GE Technotron & Honeywell Chronotherm Thermostats

Our photo illustrates General Electric's Telechron thermal control (room thermostat) first produced in 1933.

This was probably the first clock-controlled automatic set-back residential wall thermostat produced in the U.S. The top of the thermostat is hinged to permit acces to its interior for wiring.

GE Telechron Thermal Control (thermostat) is described by the U.S. Smithsonian Institute's National Museum of American History:

General Electric manufactured this Thermal Control thermostat around 1933. The thermostat came equipped with a Telechron synchronous motor that powered the clock attached to the thermostat.

The clock allowed the furnace to turn on and off at a certain time, and the thermostat has two wheels on the right and the left, which allowed the home owner to set a desired temperature during the day and during the evening. - retrieved 2017/12/31,

- original source: Smithsonian Institute, National Museum of American History, Constitution Avenue, NW Between 12th and 14th Streets Washington, D.C., USA, americanhistory.si.edu/collections/search/object/nmah_1392737

Below is a later clock-thermostat more-widely sold in the U.S, the Honeywell Chronotherm wall thermostat, another clock-operated automatic day-night room thermostat.

The Honeywell Chronotherm thermostat is described in this 1950's HONEYWELL THERMOSTAT GUIDE [PDF] produced by the Minneapolis-Honeywell Regulator Company, Minneapolis 8, Minnesota, (1950) reproduced from a Dodge building products catalog. Clicking on the first page in that PDF file should return to this web article.

Excerpts from the original Honeywell Chronotherm product literature:

Honeywell Thermostat Instructions Chronotherm

The Chronotherm is an electric clock thermostat which automatically matches the room temperature to your living schedule. All day long it controls the burner to maintain the exact temperature you want.

A special 'Comfort' feature in the instrument assures extremely accurate control. It senses heat requirements quickly. There is no under-heating to cause chills, no overheating to waste fuel.

At bedtime, this never-forgetting instrument lowers the room temperature as you wish for your sleeping comfort. ... it saes up to 20% of yoru costly fuel.

Then in the morning the Chronotherm automaticallyi raises the room temperature to the daytime cofort level. ...

If you plan to leave over a week-end, it's a simple matter to save fuel while you are gone.

The handy finger-tip levers on the Chronotherm allow you to lower the temperature settings as you wish. - 1950's HONEYWELL THERMOSTAT GUIDE

Two other Honeywell thermostats sold in 1950 were the Time-O-Stat for semi-automatic day-night temperature control, and the Acratherm thermostat. We illustrate both of these below.

Room thermostats for air conditioning work and are set the same as when these devices are used for controlling heating systems. We provide lots of detail about how these devices work - see THERMOSTAT SETTING INSTRUCTIONS.

Traditional Rectangular Wall Thermostats and how they are set

On this wall thermostat the red pointer shows the current room temperature.

The black pointer at the center of the scale at the bottom of the little window shows the temperature that the thermostat has been 'set' to.

The 'Set Temperature' is the temperature that the room occupant is requesting.

Moving the thermostat adjustment lever (located at the top, side, or bottom of the thermostat depending on the model) will change the set temperature up or down, causing the heating or air conditioning system to turn on or off as needed.

SeeTHERMOSTAT SETTING INSTRUCTIONS.

Programmable, Digital Room Thermostats & How They are Set

Digital room thermostats are illustrated in our two photographs shown here. A modern digital thermostat uses an LCD type display to show the current room temperature along with other information.

Typically the display changes in response to pushing the thermostat control buttons.

Most digital room thermostats are 'programmable' - you can set the thermostat to set back the room temperature at night (in heating mode, for example) and many models allow different time and temperature settings both throughout the day and for individual days of the week as well.

Our digital thermostat shown at left indicates the time (5:43 PM) in the left side of the display and the current temperature (53 °F) in the right side of the display.

With the thermostat's plastic cover 'shut' it's operation is very simple, just showing up and down arrows that temporarily call for a higher or lower room 'set' or 'desired' temperature.

We opened the plastic thermostat cover to show additional detailed controls and instructions.

Our Favorite Room Thermostat - The Honeywell RTH2300 / RTH221

The Honeywell RTH2300 / RTH221 series room thermostats are easy to program, permit different weekday and weekend programs, and include a 'hold' button that is invaluable for keeping the thermostat at a fixed setting without losing the whole program.

Honeywell displays a 'Rated Overall Best Brand' sticker on the packaging indicating that this model received a 'Best' rating by an independent Frost & Sullivan study.

At THERMOSTAT SWITCHES, INTERNAL we describe how to set this thermostat's internal 'Gas' or 'Oil' slide switch.

At TROUBLESHOOT ACCURACY & RESPONSE of THERMOSTATS we describe the accuracy of this thermostat, typically +/- 1° F.

We describe the operation of a typical digital room thermostat for heating or air conditioning later in this article at DIGITAL ROOM THERMOSTAT OPERATION

A simpler programmable Honeywell® digital room thermostat is show in our photo at left. This is a Honeywell CT2700 Electronic Round Programmable Thermostat.

The thermostat is showing the current time (12:15 PM) and current room temperature (67 °F).

This unit does not provide additional buttons under a cover. But by pressing the center 'Set' button the display changes to allow the user to set a desired time and temperature setting for day and night time temperatures.

At THERMOSTAT SWITCHES, INTERNAL we discuss setting the thermostat's internal F/E toggle switch.

Watch out: we installed and tested two of these thermostats over several years of use. While the device is simple, un intimidating, and easy to program, the lack of a 'hold' feature was annoying and required more fooling around; we also would have liked an additional daytime automatic setback period that this device doesn't offer.

But the worst discovery was that our oil burner was short cycling, sometimes turning on for just a few seconds - a problem that we finally traced to a defect in one of these thermostats. (The problem ceased when we swapped in our preferred thermostat shown above). We also found the flat cable wiring of this thermostat very fragile - eventually the display cable simply detached itself from its contacts.

The Nest™ Learning Thermostat - home automation features include buiding occupancy monitoring & communicating with the Nest Protect Carbon Monoxide & Smoke Detector

'The Nest Learning Thermostat' is an electronic device that can control room temperatures and possibly other components connected to or installed as part of a home automation system. We have installed three of these in our test building and will report further on ease of installation, programming, and use as well as using and adjusting the Nest thermostat remotely from your cellphone, computer, or tablet.

Photo: the Nest® Learning Thermostat on demonstration display at a Home Depot store in 2013. [Click to enlarge any image]

Nest Learning Thermostat Installation & Use Article Series

• NEST LEARNING THERMOSTATS - home
  • NEST THERMOSTAT WIRING INSTRUCTIONS for use with their Energy Kinetics 2000 MANAGER [PDF]

Radiator Thermostats & Baseboard Thermostats, Automatic - TRVs & How They are Set

Several manufacturers provide thermostatically-controlled radiator valves (Armstrong, Danfoss, Hoffman Specialty, Jacobus (Maid'O'Mist) and others).

Automatic radiator/baseboard valves provide thermostatic controls that can be installed on individual hot water radiators, steam radiators, or heating baseboards. The automatic radiator or baseboard valve will automagically open or close to attempt to control room temperature to the desired level.

Shown at left is an adjustable individual thermostatic control installed on a hot water radiator in Molde, Norway.

For details see RADIATOR VALVES & HEAT CONTROLS This article describes these automatic or thermostatically controlled radiator valves (such as the Armstrong RV-4) that will allow you to set the desired room temperature.

Also see RADIATOR STEAM VENTS, 1-PIPE SYSTEMS for a description of automatic steam vents used to control the rate at which steam heat radiators will get hot. Automatic steam vents can help balance the delivery of otherwise uneven steam heat throughout a building.

Remote Control Room Thermostats for Heating and Air Conditioning & How to Use Them

Remote control thermostats such as the unit shown at left are usually used with air conditioning or heating split systems using an outside compressor/condenser unit and one or more indoor wall-mounted cooling or heating units..

The thermostat controls in the hand-held remote control communicates with a wall-mounted air conditioner or heater using infra red signals.

The open finned area at the bottom of this Sanyo control (at the left in our photo) permits ambient air to enter the control for purpose of sensing the air temperature.

A control such as this Sanyo™ unit can be quite sophisticated and include automatic set back temperatures, timers, etc.

See SPLIT SYSTEM AIR CONDITIONERS & HEAT PUMPS for details, including troubleshooting and fixing remote control thermostats themselves

as we describe in detail at SPLIT SYSTEM AIR CONDITIONERS & HEAT PUMPS-FAQs

Hand held A/C remote control does not seem to be working

Have a hand held remote for TCL air-conditioner (split model TAC-30CHS/G). when we set temperature, conditioner blinks what you want it to be, then it goes to inside temperature (suppose to do this) but then it quickly jumps to 34 degrees & switches off. Guessing it is thermostat? Anne Webber 9/2/11

Reply:

Anne, sounds odd to me too. Try

• putting a new battery in the hand held remote and reinitializing it
• turn off all system power when you're not already in the middle of a cooling cycle and leave it off for a minute - or if you were in cooling cycle, wait an hour, then turn power back on - resetting everything.
• be sure you've got clear line of sight between the remote A/C controller and the receiving unit
• be sure that the wall mounted thermostat (if there is a separate one) is properly located where it can see or communicate with the indoor wall mounted blower assembly.

If those steps don't fix the problem and you don't see more help in the installation and use manual, it's time to ask for an HVACR service call as there could be a bad controller, thermostat, or control board.

Outdoor Thermostats on the Heat Pump Compressor-Condenser Unit

Heat Pump Outdoor Thermostats are used to control the turning on and off of backup heat.

Our photo (left, courtesy of Neal Renn shows the thermostatic control unit in the outdoor compressor/condenser unit of a residential heat pump.

See HEAT PUMP THERMOSTAT, OUTDOOR and BACKUP HEAT for HEAT PUMPS

Also see Detailed Case of a Heat Pump that Put out Heat when Cooling was Required

Choices of Room Thermostat Models, Brands, Features

In the article above and at Related Links (near page top) we describe the installation and use of most types of room thermostats used for heating, cooling, even dehumidification in buildings. But there are hundreds of models and features available.

The largest selection of room thermostats we find anywhere is at Grainger who has over 250 models in their online catalog. http://www.grainger.com - but beware not every thermostat description necessarily names all features.

Room Thermostat Temperature Sensor Mechanisms

Our photograph illutrates a traditional bimetallic spring used in many thermostat interiors to sense and respond to room temperature.

A variety of methods are used to sense room temperature and to communicate that data to the thermostat's heating or cooling switching mechanism:

Bimetallic Element thermostats use a bimetallic spring consisting of strips of two different metals fused together, typically into a coil shape. As room air temperature causes the two metals to expand or contract at different rates, the effect is that the spring coils up or un-coils, moving a switch that turns heating or cooling or or off.

Bellows Element thermostats are filled with a volatile liquid that vaporizes at temperatures typically found indoors. As the liquid vaporizes pressure inside the bellows expands, translating temperature change into the movement of a contact to turn heating or cooling on or off in response to building temperature.

Thermistor-type thermostats use a tiny solid-state electronic component, a type of resistor whose electrical resistance changes in response to temperature. By combining the thermistor with appropriate additional circuits and controls the thermostat uses the change in resistance to control the switching of the thermostat's control of cooling or heating on or off in response to room temperature.

For details: at TEMPERATURE RESPONSE of ROOM THERMOSTATS we give a detailed description of how room thermostats sense & respond to room temperature, and

at HEAT ANTICIPATOR ADJUSTMENT

and THERMOSTAT SWITCHES, INTERNAL we explain methods used to fine-tune thermostat operation in response to temperature swings, thus adjusting the burner on-cycle or fan operation if the heating system uses a fan.

Also see THERMOSTAT CALIBRATION where we discuss the accuracy and calibration of room thermostats.

Steam Heat Room Thermostats, Wall-Mounted

Room thermostats used to control steam heat may vary from their cousins illustrated above, or not - depending on just what the thermostat is controlling. In a residential application a standard room thermostat works fine to turn on or off the steam boiler.

But in larger buildings you may find that the room thermostat for steam heat is controlling a valve or relay that admits steam to radiators in one room or in just one section of a building.

In our photo at left, this wall thermostat controls steam heat in a college office in Poughkeepsie, NY.

[Click to enlarge any image]

The upper scale indicates the current room temperature.

The lower dial-scale is the set-temperature adjustment on this thermostat. The thermostat controls a steam radiator valve that in turn admits or shuts off heat into the space managed by this device.

RADIATOR & BASEBOARD THERMOSTATS, Automatic - TRVs provide an alternative that can control individual hot water or steam radiators in buildings.

Thermostat Accuracy: Settings vs Room Temperature

Reader Question: Honeywell RTH 2300 thermostat in cool mode accuracy

13 Aug 2015 Bryan said:

Office environment with a HONEYWELL RTH2300 thermostat . . . in Cool mode Fan On and set to 75F Hold . . . cooling does not click on until 77F reached on display temp . . . and does not click off until 73F reached on display temp . . . I would think cooling should click on when above 75F . . . ie at 76F . . . and click off when below 75F . . . ie at 74F . . . is this operating within standard tolerance? . . .

is the thermostat defective? . . . is there any means to rectify to hold at 75F?

Right now there is a 4 degree variance which at 77F is slightly too warm and at 73F is slightly too cool . . . would be better clicking on at 76F and off at 74F.

Thought about changing the batteries but don’t think that should have any effect as cooling is clicking on and off OK and display reading OK just at higher and lower temps than the setting.
Any comments or suggestions to rectify would be greatly appreciated.
Thanks, Bryan

Reply:

Good question, Bryan. I like the Honeywell RTH 2300 thermostat series an have installed a number of them without having the trouble you describe.

I'd expect the thermostat to respond just as you do. And I'm doubtful that batteries are the problem.

Looking at Honeywells' FAQs for the RTH2300 the company says that the thermostat accuracy is +/- 1 degree Farenheit

Your thermostat is designed to control temperature to +/- 1 F.

How often your heat turns on and off depends on may factors including the type of heating system you have, as well as how much your system needs to run to maintain your temperature setting (in other words, how cool or cold it is outside). A typical forced air system will cycle about five times in an hour (5CPH), this is normal. A typical hot water system would cycle less then that.

See TEMPERATURE RESPONSE of ROOM THERMOSTATS for details.

A Guide to Using Wall-Mounted Room Thermostats - How to Set the Thermostat

This topic has been moved to its own article now found at THERMOSTAT SET PROCEDURE

How to Set a Room Thermostat To the Desired Temperature

See THERMOSTAT SET to DESIRED TEMPERATURE

How a Digital Room Thermostat Works

See HOW DIGITAL THERMOSTATS WORK

Backup Batteries & Default Programs for Digital Room Thermostats: blank thermostat display problems

Some programmable digital room thermostats include an internal battery that will allow the device to remember the program that you have set even if there has been a power outage. This topic has been moved to its own article at THERMOSTAT BACKUP BATTERIES - for temporary or full time operation.

Heating & Cooling Control Thermostat Troubleshooting Guide

We have moved and expanded this discussion to a separate article found at THERMOSTAT DIAGNOSTIC GUIDE - link given just below.

Question: Honeywell RTH2300 thermostat not responding properly to room temperature

12 August 2015 Bryan said:
Office environment with a HONEYWELL RTH2300 thermostat . . . in Cool mode Fan On and set to 75F Hold . . . cooling does not click on until 77F reached on display temp . . . and does not click off until 73F reached on display temp . . . I would think cooling should click on when above 75F . . . ie at 76F . . . and click off when below 75F . . . ie at 74F . . . is this operating within standard tolerance? . . . is the thermostat defective? . . . is there any means to rectify to hold at 75F?
Right now there is a 4 degree variance which at 77F is slightly too warm and at 73F is slightly too cool . . . would be better clicking on at 76F and off at 74F.
Thought about changing the batteries but don’t think that should have any effect as cooling is clicking on and off OK and display reading OK just at higher and lower temps than the setting.
Any comments or suggestions to rectify would be greatly appreciated.
Thanks,

Reply: check for dirt, dust, or drafts before replacing a non-responsive thermostat

Good question, Bryan. I like the Honeywell RTH 2300 thermostat series an have installed a number of them without having the trouble you describe.

I'd expect the thermostat to respond just as you do. And I'm doubtful that batteries are the problem.

1. FIRST: inspect the thermostat closely to be sure that no clod of dust or crud is blocking the little thermistor that senses temperature.
2. SECOND: check that the thermostat is not being confused by external conditions such as location on a wall that exposes the thermostat to hotter or cooler temperatures than the actual room temp. A subtle example can be a convection current running through an uninsulated interior wall cavity that is blowing cool air into the thermostat from its back-side through the wiring opening in the wall. This is probably not your problem since if the thermostat were being thrown off by sunlight, wall mounting location, or drafts, I'd expect its room temperature to reflect that influence. You'd see instead a gap between the room temperature shown by the thermostat's indicator and an independent measurement of room temperature say in the middle of the room.

A programmed setting can also confuse us about how the thermostat should be responding if a thermostat is running under a program whose settings are not what we thought.

But if you've got the thermostat in HOLD mode then it ought to respond to temperature changes around the hold temperature setting. Double check that you see the word 'HOLD' in the display.

This Honeywell RTH2300 thermostat has some self-diagnosing circuitry which I summarize:

• It will display low battery ('Lo Batt') for 60 days before the battery is dead.
• HI: the ambient temp is above 120F
• LO: the ambient temp is below 32F - these are the operating limits of the device
• E1 or E2 = bad sensor, replace the thermostat

I'd give the company a call to ask about the response you're experiencing:

Call Honeywell Customer Care toll-free at 1-800-468-1502 or see the company's consumer website at DIYthermostats.honeywell.com.

Also see THERMOSTAT CALIBRATION where we discuss the accuracy and calibration of room thermostats.

...

Continue reading at THERMOSTAT DIAGNOSTIC GUIDE or select a topic from closely-related articles below, or see our complete INDEX to RELATED ARTICLES below.

Or see THERMOSTATS, DIAGNOSTIC FAQs

MANUALS & PARTS GUIDES - HVAC - home

Suggested citation for this web page

THERMOSTATS, HEATING / COOLING at InspectApedia.com - online encyclopedia of building & environmental inspection, testing, diagnosis, repair, & problem prevention advice.

INDEX to RELATED ARTICLES: ARTICLE INDEX to HVAC THERMOSTATS

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Technical Reviewers & References

• [1] Proliphix Corporate Headquarters, 3 LAN Drive Suite #100, Westford, MA 01886 Phone: +1.978.692.3375 Toll Free (U.S.): 866-IP-LIVING (866.475.4846) Fax: +1.978.692.3378 - Sales: sales@proliphix.com Marketing: marketing@proliphix.com Customer support: support@proliphix.com http://www.proliphix.com/ - quoting from the company's website:
  All Proliphix Network Thermostats come with our free Uniphy Remote Management Service. This unique offering lets you monitor and control your HVAC systems by simply pointing your Browser to our secure Proliphix Web Site. Enjoy the convenience of programming a thermostat from any location, using a simple graphical interface. No computer equipment or software is required. And since Proliphix takes care of the network configuration for you, you’ll be up and running in no time. We’ll even proactively monitor your thermostats and send you an immediate email or SMS message when an HVAC problem is detected.
• [2] 'The Nest Learning Thermostat', Nest Thermostat, 900 Hansen WayPalo Alto, CA 94304, Tel: 855-4MY-NEST, Email: info@nest.com, website http://www.nest.com/, retrieved 1/24/2013.
• [3] Honeywell Controls, the company wants you to use their contact form at this web page: http://www51.honeywell.com/honeywell/contact-support/contact-us.html
  Honeywell Consumer Products, 39 Old Ridgebury Road Danbury, CT 06810-5110 - (203) 830-7800
  World Headquarters, Honeywell International Inc., 101 Columbia Road, Morristown, NJ 07962, Phone: (973) 455-2000, Fax: (973) 455-4807 1-800-328-5111
• [3a] Honeywell Tradeline T87T Universal Thermostat Installation Instructions for the Trained Service Technician', Honeywell International Inc. Honeywell Limited—Honeywell Limitée1985 Douglas Drive North 35 Dynamic DriveGolden Valley, MN 55422 Scarborough, Ontario M1V 4Z9, 60-0830—4 G.H. Rev. 8-02, retrieved 12/1/2013 Website: www.honeywell.com
• [4] White Rodgers Thermostats and HVAC controls,
  Homeowner information: http://www.emersonclimate.com/en-US/brands/white_rodgers/Pages/wr-homeowner-info.aspx
  Contractor information: http://www.emersonclimate.com/en-US/brands/white_rodgers/wr_contractor_info/Pages/white-rodgers-contractor-info.aspx
  White Rodgers Product Catalog (don't misspell the company's name as White Rogers Thermostats) -
  http://www.emersonclimate.com/Documents/thermostats.pdf - Thermostat Catalog
• [5] Domestic Central Heating Wiring Systems and Controls, 2d Ed., Raymond Ward, Newnes, ISBN-10: 0750664363, ISBN-13: 978-0750664363, Quoting from Amazon.com:
  This unique A-Z guide to central heating wiring systems provides a comprehensive reference manual for hundreds of items of heating and control equipment, making it an indispensable handbook for electricians and installers across the country. The book provides comprehensive coverage of wiring and technical specifications, and now includes increased coverage of combination boilers, recently developed control features and SEDBUK (Seasonal Efficiency of Domestic Boilers in the UK) boilers ratings, where known.
  In addition to providing concise details of nearly 500 different boilers fuelled by electric, gas, oil and solid fuel, and over 400 programmers and time switches, this invaluable resource also features numerous easy-to-understand wiring diagrams with notes on all definitive systems. Brief component descriptions are provided, along with updated contact and website details for most major manufacturers.
• [6] 'Automatic Oil Burner Controls - Thermostats', Domestic and Commercial Oil Burners, 3rd Ed., Charles H. Burkhardt, McGraw Hill, 1969 (and later editions), ASIN B0000EG4Y8
• Hunter Fan2500 Frisco Ave.Memphis, TN 38114888-830-1326www.hunterfan.com
• [7] Fuel Oil & Oil Heating Magazine, 3621 Hill Rd., Parsippany, NJ 07054, 973-331-9545
• [8] Domestic and Commercial Oil Burners, Charles H. Burkhardt, McGraw Hill Book Company, New York 3rd Ed 1969.
• [9] National Fuel Gas Code (Z223.1) $16.00 and National Fuel Gas Code Handbook (Z223.2) $47.00 American Gas Association (A.G.A.), 1515 Wilson Boulevard, Arlington, VA 22209 also available from National Fire Protection Association, Batterymarch Park, Quincy, MA 02269. Fundamentals of Gas Appliance Venting and Ventilation, 1985, American Gas Association Laboratories, Engineering Services Department. American Gas Association, 1515 Wilson Boulevard, Arlington, VA 22209. Catalog #XHO585. Reprinted 1989.
• [10] The Steam Book, 1984, Training and Education Department, Fluid Handling Division, ITT [probably out of print, possibly available from several home inspection supply companies] Fuel Oil and Oil Heat Magazine, October 1990, offers an update,
• [11] Principles of Steam Heating, $13.25 includes postage. Fuel oil & Oil Heat Magazine, 389 Passaic Ave., Fairfield, NJ 07004.
• [12] The Lost Art of Steam Heating, Dan Holohan, 516-579-3046 FAX
• Principles of Steam Heating, Dan Holohan, technical editor of Fuel Oil and Oil Heat magazine, 389 Passaic Ave., Fairfield, NJ 07004 ($12.+1.25 postage/handling).
• [13] 'Residential Steam Heating Systems', Instructional Technologies Institute, Inc., 145 'D' Grassy Plain St., Bethel, CT 06801 800/227-1663 [home inspection training material] 1987
• [14] 'Residential Hydronic (circulating hot water) Heating Systems', Instructional Technologies Institute, Inc., 145 'D' Grassy Plain St., Bethel, CT 06801 800/227-1663 [home inspection training material] 1987
• [15] 'Warm Air Heating Systems'. Instructional Technologies Institute, Inc., 145 'D' Grassy Plain St., Bethel, CT 06801 800/227-1663 [home inspection training material] 1987
• [16] Heating, Ventilating, and Air Conditioning Volume I, Heating Fundamentals,
• [17] Boilers, Boiler Conversions, James E. Brumbaugh, ISBN 0-672-23389-4 (v. 1) Volume II, Oil, Gas, and Coal Burners, Controls, Ducts, Piping, Valves, James E. Brumbaugh, ISBN 0-672-23390-7 (v. 2) Volume III, Radiant Heating, Water Heaters, Ventilation, Air Conditioning, Heat Pumps, Air Cleaners, James E. Brumbaugh, ISBN 0-672-23383-5 (v. 3) or ISBN 0-672-23380-0 (set) Special Sales Director, Macmillan Publishing Co., 866 Third Ave., New York, NY 10022. Macmillan Publishing Co., NY
• [18] Installation Guide for Residential Hydronic Heating Systems
• [19] Installation Guide #200, The Hydronics Institute, 35 Russo Place, Berkeley Heights, NJ 07922
• [20] The ABC's of Retention Head Oil Burners, National Association of Oil Heat Service Managers, TM 115, National Old Timers' Association of the Energy Industry, PO Box 168, Mineola, NY 11501. (Excellent tips on spotting problems on oil-fired heating equipment. Booklet.)
• [21] Trane TCONT800 Series Touch Screen Programmable Comfort Control Ownes Guide, American Standard, Inc., Troup Highway, Tyler TX 75711, January 2005, Telephone: Customer Service: 1-877-3381, website: www.trane.com

Books & Articles on Building & Environmental Inspection, Testing, Diagnosis, & Repair

• Our recommended books about building & mechanical systems design, inspection, problem diagnosis, and repair, and about indoor environment and IAQ testing, diagnosis, and cleanup are at the InspectAPedia Bookstore. Also see our Book Reviews - InspectAPedia.
• ...

• Carson, Dunlop & Associates Ltd., 120 Carlton Street Suite 407, Toronto ON M5A 4K2. Tel: (416) 964-9415 1-800-268-7070 Email: info@carsondunlop.com. The firm provides professional home inspection services & home inspection education & publications. Alan Carson is a past president of ASHI, the American Society of Home Inspectors. Thanks to Alan Carson and Bob Dunlop, for permission for InspectAPedia to use text excerpts from The Home Reference Book & illustrations from The Illustrated Home. Carson Dunlop Associates' provides extensive home inspection education and report writing material.
  • The Illustrated Home illustrates construction details and building components, a reference for owners & inspectors.
    Special Offer: For a 5% discount on any number of copies of the Illustrated Home purchased as a single order Enter INSPECTAILL in the order payment page 'Promo/Redemption' space.
  • TECHNICAL REFERENCE GUIDE to manufacturer's model and serial number information for heating and cooling equipment, useful for determining the age of heating boilers, furnaces, water heaters is provided by Carson Dunlop, Associates, Toronto - Carson Dunlop Weldon & Associates
    Special Offer: Carson Dunlop Associates offers InspectAPedia readers in the U.S.A. a 5% discount on any number of copies of the Technical Reference Guide purchased as a single order. Just enter INSPECTATRG in the order payment page 'Promo/Redemption' space.
• The Home Reference Book - the Encyclopedia of Homes, Carson Dunlop & Associates, Toronto, Ontario, 25th Ed., 2012, is a bound volume of more than 450 illustrated pages that assist home inspectors and home owners in the inspection and detection of problems on buildings. The text is intended as a reference guide to help building owners operate and maintain their home effectively. Field inspection worksheets are included at the back of the volume.
  Special Offer: For a 10% discount on any number of copies of the Home Reference Book purchased as a single order. Enter INSPECTAHRB in the order payment page 'Promo/Redemption' space. InspectAPedia.com editor Daniel Friedman is a contributing author.
  Or choose the The Home Reference eBook for PCs, Macs, Kindle, iPad, iPhone, or Android Smart Phones.
  Special Offer: For a 5% discount on any number of copies of the Home Reference eBook purchased as a single order. Enter INSPECTAEHRB in the order payment page 'Promo/Redemption' space.
  Building inspection education & report writing systems from Carson, Dunlop & Associates Ltd
• Commercial Building Inspection Courses - protocol ASTM Standard E 2018-08 for Property Condition Assessments
• Home Inspection Education Courses including home study & live classes at eleven colleges & universities.
• Home Inspection Education Home Study Courses - ASHI@Home Training 10-course program.
  Special Offer: Carson Dunlop Associates offers InspectAPedia readers in the U.S.A. a 5% discount on these courses: Enter INSPECTAHITP in the order payment page 'Promo/Redemption' space. InspectAPedia.com editor Daniel Friedman is a contributing author.
• The Horizon Software System manages business operations,scheduling, & inspection report writing using Carson Dunlop's knowledge base & color images. The Horizon system runs on always-available cloud-based software for office computers, laptops, tablets, iPad, Android, & other smartphones