Honeywell CT87B ROUND HEATING&COOLING MECHANICAL THERMOSTAT - WHITE Heater - Answered Questions & Fixed issues

the two wires are hooked to the baseplate at the R terminal and the W terminal. there may be a switch somewhere on thermostat for electric or gas heat. make sure its in gas mode. make sure batteries are fresh and put in correctly in regards to polarity. make sure furnace is on when doing any settings with the thermostat. make sure themostat is set to "heat". make sure themostat is calling for heat (turn way up to be sure its doing that) . check the troubleshooting guide that came with the new thermostat.

Most thermostat have a dead band setting that you can set yourself.
Maybe your dead band is set 1 or 2 degrees above setpoint so unit would run to satisfy deado band

Your electric bill seems extraordinarily excessive. To comment about your heating and thermostat I would need to understand it and your description doesn't provide enough detail. A thermostat is only as good as the heating system. Smooth response and a uniform temperature is only possible if the heating system has capacity to spare in order to provide a quick recovery and rapid cycling. Perhaps the fan keeps running to maintain a more uniform temperature. You didn't mention what the outside ambient temperature is during the night but setting the thermostat at 74 does seem rather extravagant for sleeping. 68, winter weight pyjamas and a thicker duvet would be a much more economic temperature, especially in these times of climate change. Mobile homes aren't noted for their insulating qualities and advancing age never improves the situation. I wager if you asked someone to bring a thermal imaging camera you would discover a great deal of your heating budget is spent warming the outside, I expect much heat is escaping through the roof, walls and windows. The walls and roof of a mobile home simply are not thick enough to provide even the minimum thickness of insulation a permanent dwelling should have had 30 years ago...

sounds like your yellow should go to either white or yellow and a jumper installed between the 2. then test both heating and cooling, may need to make co figuration change on how your reversing valve is energized. If you need further help, reach me via phone at https://www.6ya.com/expert/thomas_092728000e6acb79

how old is unit? Sounds like it may be short cycling which could be do to it going off on limit.

yes it can but also low freon can do the same turn stat all the way down and observe unit now turn all the way up if unit still doing the short cycle at either temp range stat is faulty if when stat was on high temp zone and unit turned off will need to check on the system for low freon but if your having problems with stat replace its cheap insurance against higher electric bills and possible damage to the a/c system

'Override' condition is the condition where the thermostat is manually bypassing the scheduled event. It goes into 'override' when you push the 'override' button and goes out of 'override' when you either push 'override' again or the 'run program' button. If it is not a programmable time frame, the typical 'override' length is 2 hours.

Here is the user manual for your unit. https://www.manualowl.com/m/Honeywell/CT87B/Manual/134033 Look at parts 7&8 of the manual. In section 8 there is a notation about the anticipator pointer adjustment that should solve your problem.

on these thermostats remove the outer ring cover and in the lower right side you will see a slide adjustment. move it i believe left for closer cycles and right for longer cycles. it should be 2* on either side of set point. remember that the fan is not furnace shut off.and turning back and forth will not tell you anything. just set it and see how it works then change it again if you need to

Adjust the high limit on the control.

is there HOLD button?

On your thermostat - R is the power in terminal. Y is the cooling out. W is the heating out. (G is fan out). It does not matter which wire goes to R, the other should go to W - if no heat with a call, the thermostat is bad.

ok did that help

Maybe click on this........https://customer.honeywell.com/resources/techlit/TechLitDocuments/69-0000s/69-1959EFS.pdf

Yellow- air conditioning. White- heating. Green- blower fan. Red- 24 volt power . Blue- common wire not always used on battery thermostats.

There is a filling loop on the cold feed in to the boiler .A hose !! or a valve you can turn on again on the cold feed in

I have the same boiler with a similar issue. The water is more than likley leaving the system from the pressure relief valve, which will be routed outside. It sounds like you have lost the pressure in your expansion tank, which is inside the boiler. With the boiler pressure at zero and the power isolated, the expansion tank can be accessed from a panel at the top of the boiler on the right hand side. You will see a valve on the red expansion vessel like the one on a car tyre and can be pressurised with a car tyre air pump. I think from the manual the pressure should be about 1 bar, but it depends on the length of pipework on your system. A competent boiler engineer should be able to sort this out, but it may be that your valve is leaking, or the expansion vessel has failed and the problem will occur again.

You need a specific thermostat for a Wall Furnace it is a Millivolt Thermostat and not a 24v standard thermostat....usually it will work anyway however if the powerpile (generator produces millivolts from the pilot light) is weak it may not be producing enough...or the Pilot light may be dirty and lazy...won't produce enough millivolts ...or you can have bad or dirty contacts or connections....or a combination of any of the above.....a 24v Thermostat and particularly a non-mercury thermostat has too much resistance in it for a millivolt system....as your Wall Furnace (other than the fan) runs on less than 1 volt

Does the power vent come on? If so you probably need either a new ignitor or a new circuit board.

I'm not sure if you received my clarification request or not. I will assume that the only colors you have for wire are what you stated in your problem description. Attach the red wire to R, the green wire to G, the white wire to W and the blue wire to Y..

After you have done this, make sure to look in the air handler to be sure the wires are tied to the same terminals inside as there should be a terminal board for them.

I hope this helps you get cool.

Rev