How to Install a Programmable Thermostat

programmable thermostat installationInstalling a programmable thermostat is not unlike installing any other thermostat for your HVAC system. The key is to get the right thermostat for your HVAC system and to make sure it is wired properly. Many thermostat manufacturers provide detailed installation instructions with their thermostats to make sure you have all the information you need to install the thermostat properly. Sometimes the instructions that come with the new thermostat can be vague or even confusing and that is what we want to help you with here at High Performance HVAC. Please see our other articles for installing thermostats on our other pages to help you with your thermostat installation. Below are some good tips and detailed instructions on installing your new programmable thermostat. And don’t forget after the new programmable thermostat is installed you still have to program it.

heat pump thermostat wiring chart

 

The above chart will help you understand the wiring terminals and color designations for a heat pump. If you are installing a the programmable thermostat for a boiler it should only require two wires. It is a two wire thermostat installation. This is for a battery powered thermostat and the two wires are only for the switching on and off of the boiler for heating.

two-wire thermostat control

Wiring your programmable thermostat for boiler or furnace control with only two wires will work just fine except you will need to keep replacing the batteries on a regular basis. If you want to have the thermostat powered by the transformer the wiring needs to be as in the following graphic:

3 wire thermostat control

Whereas the common wire from the transformer goes into the thermostat to provide a complete 24 volt circuit for thermostat power. For an air conditioner the wiring should be as follows:

Air Conditioner

 

These are the basic wiring diagrams for installing a programmable thermostat. There are some other combinations for wiring a programmable thermostat but the information here will cover 90% of the combinations most people need. If you have something different or unique email us using the contact form and describe to use what you have. We will respond to you with some follow up questions and ask you to send us some photos of what you have. Then we will respond to you with our advice on how to wire your thermostat.

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Wiring Diagrams for Programmable Thermostats

Honeywell VisionPro and Heat Pump – Programming and Settings

Honeywell VisionPro and Heat Pump - Programming and SettingsRichard, I have a Honeywell Vision Pro Thermostat. I was wondering how I can program the settings to save money? It was recently installed six months ago and I want to make sure it is programmed to get the best out of it for a heat pump. At this point I do not believe I have saved money and was told I could save 10% or more with a programmable thermostat. Please help me with the appropriate settings and give me some insight that would help me save money. Thank you and I look forward to your answer.

The VisionPro can save you money but with all things being relative the temperatures this year can be colder than the temperatures last year so the system would run more thereby costing you more money.

Another factor is has anything changed in the home? Maybe a lot of people going in and out or a window cracked open somewhere?

Is it programmed properly? If it is not then you will likely see no savings depending on the settings. Or if someone keeps changing it to turn the temperature up it won’t save you any money.

There are 4 settings:

Wake – this should be set when you wake up in the morning. Preferably 30 minutes to an hour so the house will be warm or cool when you wake. Example – if it is winter at night when you go to bed the night setback goes to say 60°. You wake up at 6am so at 5:30 am you set the program to turn the heat on for a set point of 70°.

Leave – this should be the time approximately 30 minutes before you leave. The temperature gets setback so the system will not run while you are at work. Example – The temperature set point while you are getting ready for work is 70°. You leave the house at 7:30 am. So the thermostat should be set back to 60° at 7 am so while you are at work the system will only run when the temperature goes down to 60 degrees.

Return – this should be set to approximately 30 minutes to an hour before come back home for the day. Example – you return home at 5 pm. The program should be set for 70° to turn on at 4:30 pm so the house is warm when you get home.

Sleep – this should be set to set back temperature for when you are sleeping. Example – in the winter set it down to say 60° about 30 minutes before you go to bed.

HVAC Electric Heating Basics

Electric Heat Strips for an Electric Furnace or Heat Pump Back-up Heating

With heat pumps the temperature differential is typically 3° for the auxiliary heat to kick in and assist the heat pump so if the temperature in the house is 60° and you program it to come on and bring the temperature up to 70° you will have the auxiliary heat come which it is common in most heat pump installations to have electric heat. Electric heat is 100% efficient but it costs more per BTU to produce than the heat pump refrigeration cycle will cost you. So from 60° to 67° you will be using auxiliary heating in addition to the heat pump if the differential is set at 3° (it is adjustable in the installers program set up). You could expand that setting to to reduce that cost however when the temperature gets really cold (below 38°) then the differential is a factor in your warmth because the second stage or auxiliary heating will not kick on until the differential is met. So if you have the thermostat set for 70° and the differential is 3° the auxiliary heating will not kick in until 67°. If you make that a 4 degree differential in the installers set up program the back-up or second stage heating will come on until 66° and you can become uncomfortable.

When the temperature outdoors falls below around 38 degrees the heat pump mechanical heating will begin to stop keeping up with demand. This is the reason why air source heat pumps are installed in southern regions and not really good for northern regions as the temperatures in the winter are frequently lower than 38°. So if the temperatures in the region where you live rarely fall below 38° then the differential setting will not make that much of a difference but if you live in the mid-atlantic region then it is probably not a good idea to reset the differential anymore than 3°.

Using the VisionPro thermostat in that fashion will save you money. Now saying all that if you have settings like that and if you still have problems it could be something to do with your heat pump. The best thing to do, after checking the thermostat program, is to call a heat pump repair service company to check it out. I hope that gave you some insight into your thermostat and your potential problem. Good Luck.

High Performance HVAC Air Conditioning and Heating & Cooling Systems

Honeywell VisionPro and Heat Pump – Programming and Settings

Basic Thermostat Wiring Colors – AC Systems

Always remember when changing a thermostat for a new thermostat to take a photo of the colors and where they go on the old thermostat or get a pencil and paper and write it down. It is better to take a good up close photo of the old thermostat what terminals the colored wiring are terminated. Nearly everyone has a camera on their cell phone.

See the important notes below for further instructions

Basic Thermostat Wiring Colors Air Conditioning
Thermostat Terminal Wire Color What is Does
R Red 24 Volts AC/Heat Single Transformer
RC Red 24 Volts for Dual Transformer – AC♦
RH Red 24 Volts for Dual Transformer – Heat♦
G Green Blower Fan Control
Y1 Yellow Cooling Terminal – Condenser Control
Y2 Light Blue but Varies♣ Cooling Second Stage
W1 White Heating Control
W2 Brown or Black but Varies♣ 2nd Stage for Heat
C Dark Blue but Varies♣ Common

See our other thermostat installation advice articles.

Notes on Thermostat Wiring Colors:

♦Some HVAC systems will have a two transformer set up. A 24 Volt transformer for the air conditioner and one for the boiler or furnace. If you have a dual transformer system then you need to use terminals RC and RH. RC is for the air conditioner and RH is for the heating system.

♣The thermostat wire colors for these terminals will vary depending on the installer of the HVAC system and if they used conventional accepted colors for that terminal. This is why it is good to take a photo so you get it right the first time. You don’t know who wired the old thermostat and if they used conventional colors.

Basic Thermostat Wiring Colors – AC Systems

How to Wire an Air Conditioner for Control – 5 Wires

terminal board inside thermostat for wire terminations uses 18 gauge connectionsThe diagram below includes the typical control wiring for a conventional air conditioning system. It includes a thermostat, a condenser, and an air handler with a heat source. The heat source for a basic air conditioning system can include heat strips for electric heat or even a hot water coil inside the air handler that is fed from a water heater. Every conventional residential air conditioning system uses a 24 volt control system for the control of the system. All the relays in the system have 24 volt coils. Control boards or printed circuit boards found in modern systems utilize 24 volt control which originates from the control transformer. Standard 18 gauge thermostat wire is used for all control wiring.

Thermostat Wiring Diagram

Air Conditioner Control - Thermostat Wiring Diagram - HVAC Systems

Terminal Strip in an Air Conditioner Air Handler - Electrical Connections

Terminal Strip where wire terminations are made during installation. Typically inside the air handler

 

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Air Conditioner Control – Thermostat Wiring Diagram

HVAC Products Containing Mercury and Proper Disposal

Products Containing Mercury and the Environment including new State Laws & Regulations and pending legislation

Mercury is extremely harmful to the environment and cause severe health problems in humans and animals. For many years HVAC and HVAC Controls manufacturers have used mercury in switches. Mercury is a liquid metal and provides a good source used in many switches because of its fluidity and conductivity. From thermostats to boiler controls mercury provides a reliable and efficient switching mechanism to start and stop certain sequences in HVAC applications.

Because mercury is very harmful to the environment and because many people do not know it is harmful or they are irresponsible and improperly dispose of products containing mercury some States have come up with laws regulating products which contain mercury or there is pending legislation ban the sale and use of products which contain mercury. Manufacturers have alternative methods to control HVAC applications and have taken steps to decrease production of making products which contain mercury and increase production of replacement controls especially for the States where there is current or pending legislation.

It is important if you replace your thermostat to check to see if it has mercury before throwing it in the trash. If you see a little oval bulb with a silver liquid inside the bulb you have a thermostat which contains mercury. It is important to properly dispose of this part of your thermostat which contains mercury. Other HVAC controls which contain mercury are boiler controls especially on steam boiler systems. It is improbable that the typical homeowner or business owner will replace this control if it malfunctions but maintenance personnel and HVAC and boiler technicians should be aware of these new laws and the fact that mercury harms the environment so that they properly dispose of any product which contains mercury.

At the end of the usable life of a product which contains mercury the products which contain mercury must be recycled or disposed of in accordance with Local, State, and Federal Regulations so that the mercury in these products do not harm the environment.

Please refer to your individual state laws and regulations to determine specific requirements for disposal of any products containing mercury. Never put products which contain mercury in the trash. Call your local refuse or Disposal Company or the State Environmental Protection agency and ask how to properly dispose of products which contain mercury.

States with Current or Pending Legislation Banning the Sale or Distribution of Products which Contain Mercury*

 

State Effective Date
California July 1, 2006
Connecticut July 1, 2004
Illinois July 1, 2007
Louisiana January 1, 2007
Maine July 1, 2006
Massachusetts May 1, 2008
Minnesota August 1, 2007
New York January 1, 2008
Rhode Island January 1, 2006
Vermont January 1, 2007

*If your State is not listed check you Local, State, and Federal regulations for laws pertaining to the sale, distribution, use, and disposal of products which contain mercury. Many state, local, and even private waste disposal facilities have special collection methods for products that contain mercury.

 

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HVAC Products Containing Mercury and Proper Disposal

SilverPAC Silverstat 7 Advanced Thermostat

SilverPAC Silverstat 7 Advanced Thermostat

SilverPAC Silverstat 7 Advanced Thermostat

This thermostat is sure to save you some money in energy costs if you can get over the initial retail cost which is currently unavailable. Taking it a step further you can make some control changes to your appliances and hook them up to this thermostat so you can program on and off schedules for the appliances. We’re not talking about just your air conditioning and heating system either…………from your refrigerator freezer to your water heater to your lighting it can all be intelligently controlled and monitored with this thermostat. In my humble opinion this thermostat will definitely change your utility bill. Here are some of the key features that will help you save energy.

  • Smart Wi-Fi that has the ability to communicate with the new smart meters many utilities are installing including gas and electric meters. These new meters have the ability to send real time data to the utility companies to monitor usage.
  • SilverSTAT7 has Windows CE 6.0 R3 as the operating system with an Intel Atom processor which takes this smart thermostat well beyond the average home thermostat you can pick up at the hardware store.
  • SilverSTAT thermostat has a 7 inch touch screen and features a Smart Energy In-Home Display (IHD) so you can monitor the stat and the amount of energy your home is consuming at any given time of the day.
  • The Wi-Fi allows the SilverSTAT7 thermostat to communicate with your home network and internet services for remote monitoring.
  • 7 day programmable thermostat capabilities that works with a calender and scheduled alarm notices so you don’t forget to change the filters ever again.
  • The Windows software can also give you access to email, stock prices, real-time weather forecasts, and the price the utility company is charging for energy at specific times of the day.
  • SilverSTAT 7 thermostat can stream photos and music from wireless devices through your home network.

SilverSTAT7 Thermostat

Questions for the manufacturer include how many inputs and outputs for control functions and how much in house wiring changes need to take place for control of the appliances?

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SilverPAC Silverstat 7 Advanced Thermostat

Honeywell Chronotherm Plus 8624D Thermostat with a Trane XL19i

Honeywell Chronotherm Plus 8624D Thermostat with a Trane XL19i

I have a Honeywell Chronotherm Plus 8624D running a Trane XL19i with a Trane XV90 – all installed new in new construction in 2003. Every winter, during the morning warm-up from 66 to 70, the burners stays on for approximately 1.5 hours at 70, then rises quickly to 73 before finally shutting off. The only way to interrupt the process is to turn the system to OFF at the thermostat. The system is on AUTO with the cooling set at 75 for the winter. I have swapped the thermostats (there are two sets in the house, this is the one in the attic for the second floor) with the same results. I have not swapped the thermostat circuit boards, but I can not see a reason to. The main floor is on the same schedule, but has never done this three degree burst. I have had three different contractors out, with corresponding charges for thermostat troubleshooting with no luck. Have you ever seen this? Any thoughts? Thanks!

The Thermostat Answer

I get questions like this all the time which people email to me and it is difficult to give them a good answer simply because I’m not there observing this strange equipment or thermostat behavior. It sounds to me that you’ve eliminated the problem being the thermostat when you changed them out. You know the one in the other zone doesn’t exhibit the same behavior and the one in the zone giving you the problem didn’t exhibit the bad behavior (or three degree burst as you describe it) when you changed it to the other zone. At least that is how I’m reading it. You eliminated the Honeywell Chronotherm Plus thermostat as being the problem

Back to the Basics

I would go back to basics on this one and check the installation location of the Honeywell Chronotherm Plus. A thermostat should be located in a central located on an inside wall preferably as close to the return as possible. It should never be mounted where direct sunlight can hit it, on an outside wall, or near a window or door which leads outside. If that is okay then check the wall where the thermostat is mounted. The hole behind the Honeywell Chronotherm Plus thermostat? Is this a drafty hole where air comes in through crawl space or attic somehow? If that is the case stuff some insulation in the hole to prevent the drafty air from hitting the thermostat. Seal it off as best as you can to prevent this drafty air from hitting the Honeywell Chronotherm Plus thermostat. Offers residential commercial high performance HVAC advice concerning air conditioning heating Honeywell Chronotherm thermostat troubleshooting along with the Trane XV-90.

Lastly, Call in the Pros

honeywell thermostat and the Trane xv-90 gas furnaceThe next thing to do if this doesn’t solve the thermostat problem is to have an HVAC professional check the furnace out completely. I would schedule an appointment with you for morning furnace warm-up so I could observe this behavior myself. I would eliminate thermostat and control the furnace at the furnace to see if it still did this. The Trane XV-90 is a high efficiency model so you will an HVAC specialist to look at it. Preferably someone who has had some Trane factory training. These guys are not hard to find as Trane does a pretty good job of offering contractors classes for their HVAC Technicians. I believe it is requirement for Trane dealers (HVAC Contractors) to send their Technicians to so many classes every year so call a Trane dealer and ask for their best technician to look at this problem.

 

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Data Logging Thermostats

Honeywell Touchscreen Programmable thermostatHigh Performance HVAC Air Conditioning & Heating Thermostats

Data Logging Thermostats

1) Question: Is there a thermostat for a nursing home with a print out for temperature verification?

The answer…..

This is a touchy one and takes me back to the days when I started my HVAC career working in a hospital maintenance department. It also reminds of when I was doing service calls at a nursing home and listening to all the different residents complaining about the temperature. The fact is it is almost impossible to maintain a comfortable temperature between two different people. Someone has to make a decision on the temperature setting on the thermostat and live with all the complaints. For every person who says they are cold there will be a person who says they are hot. When I worked in the hospital sometimes I was assigned to verify temperatures. The hospital had a state of the art direct digital control system and every morning the maintenance chief would get a print out of all the room temperatures. He would also have a print out of all the complaints received the day before. He would hand them off to a couple of technicians and we would go manually verify that these rooms were maintaining what the computer print out said the temperature was in those particular zones where the complaints came from.

While some would think it was a waste of time verifying temperatures when the hospital was equipped with a state of the art direct digital control system the idea of sending a few technicians to all the rooms where the complaints were coming from gave the hospital staff and patients the idea that we truly cared about their comfort and that we really had no control over the temperature because the temperature was set by the director of the hospital via computer control system to maintain a precise temperature. We were simply there verifying that the state of the art DDC controls were maintaining the temperature as designed. Beyond that, the buck stopped at the directors desk.

There are thermostats and dataloggers one can purchase that will record temperatures over a period of some time to verify temperatures. Some are state of the art and some are very basic data logging thermostat temperature readers that will record the temperature over a specific period of time. The information is recorded on a graph or chart along with a time period. These data logging thermostats are often used by manufacturers who ship food and drug products via third party transporters and they want to make sure the transporter maintained the proper temperatures for the product as specified by the shipping agreement between the manufacturer and the transporter. Transporters and shippers most often use the term tattle-tale to describe these temperature dataloggers because it will tell the receiver if precise temperatures were maintained during the shipping process. This can be a solution to see if the proper temperatures are being maintained in any type of environment.

Other kinds of data logging thermostats include a temperature sensor you place in a specific location. These data logging thermostats are powered by batteries and typically need to be set up by hooking them up to a computer and using specific software made by the manufacturer of the data logging thermostat. After a specific period of time you retrieve the data logging thermostat and hook it back up to the computer and download the data stored in the data logging thermostat. You can put the downloaded information retrieved from the data logging thermostat into charts and graphs. Some data logging thermostats also have humidity sensors so you can record both humidity and temperature. See the data logging thermostat video below.

Another option is to check to see if the building is equipped with a Building Automation System or DDC system which controls the air conditioning and heating systems in the nursing home. If so, many of these systems record the temperatures in an archive file called a trend log. These trend logs are used most often by the maintenance staff to verify accurate temperatures and to troubleshoot intermittent problems with heating and cooling systems. The trend logs should record the temperatures of the zones around the clock and depending on how the program is set up will depend on how long this information is saved before it overwritten or dumped by the program. If the building is not equipped with a building automation or DDC system one would have to find a datalogger and probably the best place to find one of this the local HVAC outlets.

Remember, temperature or desired temperature is always different between different people. What is comfortable to you will not be comfortable for someone else. Many an argument has started over the setting of the temperature on the thermostat and unfortunately that is the way it is and probably always will be. You can bet that this problem is not unique with the nursing home where you work but it is the same in practically all nursing homes across the country and around the world. Temperature and comfort are always variable things where we must learn to tolerate a temperature we not so comfortable with because another person or a nameless director has the final say of where this temperature will be set. Perhaps the decision to set the thermostat where it is was based on budget concerns or perhaps it was based on a consensus of comfort factors among a group of people residing there. No matter where you set the thermostat not every person is going to be comfortable and there will be complaints. It’s just one of those things we have to learn to tolerate. Whenever I got a chronic complainer I always thought to myself or wondered what this person would have done 100 years ago or even a thousand years ago. These things are usually beyond our control in a public or even private place so we just need to learn to tolerate the temperature as set by the management. In many cases it is beyond our control so relax, throw another blanket on the bed or take a walk and get the circulation going. Another option is a portable fan. There is always a way to make yourself more comfortable in any environment.

Offers residential commercial high performance HVAC advice concerning temperature data logging thermostat and thermostat recorders or thermostat loggers air conditioning heating energy management

 

High Performance HVAC

Data Logging Thermostats