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Questions tagged [thermostat]

Mechanical or electrical device used to control a heating, ventilation, and air conditioning (HVAC) system, or other temperature reliant system.

4
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1answer
2k views

Why is my indoor A/C Blower randomly turning on and off only with Nest?

I recently purchased a Nest Thermostat (3rd Generation). My old thermostat was working perfectly. I wired Nest the Same exact wiring as the old thermostat which is : Y1 W1 G RH RC. With Nest, the ...
1
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1answer
12 views

C Wire in Air Handler

Can someone please help me find where to connect a C wire for my smart thermostat? Here are some pictures with descriptions. It is difficult to get to the 24v connection in the back. My schematic ...
0
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1answer
135 views

Smart Thermostat and 24 volt transformer direct to thermostat

I have a hot water boiler and separate AC system and bought a wifi smart honeywell thermostat to get a C wire- installed a 24 volt transformer that has two wires if one goes to the C where should the ...
1
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1answer
154 views

Old Thermostat with just R and Y wires?

UPDATE: this may be R and V, not R and Y, although I'm still not sure how it was set up. I am replacing an old thermostat in my house (the house is from the 60s, I'm not sure how old the thermostat ...
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1answer
46 views

Identify this programmable thermostat?

A tenant in my rental home had the programmable thermostat shown below installed by an electrician friend. Unfortunately, neither the tenant nor the friend has its instructions and can't remember ...
0
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1answer
961 views

How can I add a C-wire to a Venstar T5800 thermostat?

I am trying to replace my existing thermostat. My old thermostat has: Rh, W (coming from the heating unit). Rc, Y, G (coming from the AC unit). On the Venstar T5800, I can map as follows: Rh+Rc -...
0
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2answers
2k views

Nest thermostat - combi boiler and UFH set up question

We recently had some work done, a new open plan room, a new boiler and underfloor heating (UFH) put in. We had some confusion, a lot of which comes from not having a basic understanding of how the ...
1
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2answers
2k views

Installing Nest 3rd generation thermostat from Old Trane Weathertron Thermostat (Mercury one)

Nest is not detecting Power (Rh) Showing error that power is not connected. Please help. Installing Nest 3rd generation thermostat from Old Trane Weathertron Thermostat (Mercury one) New stat wiring:...
0
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1answer
183 views

Replacing old thermostat with 2 white wires for zone boiler heat

I am replacing our basement thermostat that had a white and orange wire together and a white and blue wire together. That is all there is. I ham trying to put in a heat only non programmable honeywell ...
0
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1answer
60 views

Furnace and Thermostat Issue

One day my parent's furnace and thermostat stopped working. The thermostat is a smart thermostat that depends on 24volts to the R and C wire. We measured voltage between the R and C wire and was ...
0
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1answer
23 views

Direct Wiring (bypass thermostat) of heatpump cooling

Last September my CT80 radiothermostat would not signal cooling despite the measured temperature exceeding the temperature setpoint. It would be nice if a relative could manually switch the cooling ...
3
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1answer
744 views

Why my baseboard heater won’t turn with new thermostat?

I have a pair of electromod basement heater. The label on each of them show them show 750/1000W. Power supply to this is 240V I am trying to replace the old manual thermostat with a progrmabale one. ...
1
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1answer
67 views

Thermostat C Wire (Possibly Unconnected)

I purchased a Honeywell RTH6500 Wifi Thermostat, which requires a C wire. My old thermostat showed a connected blue C wire. However, it was battery-powered. If I removed the battery, the thermostat ...
0
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1answer
121 views

Connect Wifi Thermostat to Goodman GMP050-3?

I'm trying to connect up a wifi thermostat to Goodman furnace, specifically the GMP050-3. I've done some reading on this but I'm still not quite sure how to go about it. Specifically, I'm not sure ...
1
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1answer
26 views

Green and red wire connected together on terminal

I am installing a smart thermostat but I found the old thermostat has the green and red wires both running to the g terminal. When installing the new thermostat I will be removing the jumper wire ...
2
votes
1answer
576 views

Can't get 3rd Gen Nest to power fan on Trane XR95 furnace

I have a Trane XR95 furnace and I replaced my original Honeywell Pro 4000 thermostat with a 3rd gen. Nest. I noticed, however, after installing the Nest that I can't get the fan to run on its own ...
0
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1answer
28 views

Complete power loss in over-the-range microwave

The over-the-range microwave in my kitchen (GE, 1500W) has completely lost power. The power loss was intermittent for a day, but then at some point it never came back. I have checked all fuses that I ...
1
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1answer
1k views

How to Wire 3 baseboard Heaters with 2 Thermostats

I have one 20 amp double pole circuit that I am planning to run 3 baseboard heaters on with 2 line voltage thermostats. I have already made sure the watt consumption for the 3 heaters will not exceed ...
2
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1answer
316 views

Installing a Hive Thermostat

I purchased a HIVE thermostat and want some assurance before I go about installing this. First of all i was wondering where to put the receiver as I thought it would just replace one of the ...
1
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1answer
419 views

Is my Nest thermostat wired correctly?

I've been having issues like the heat pump not heating. Now that it's hot outside, my A/C isn't working. Can someone tell me if my Nest thermostat is even wired correctly? If it helps any, here is ...
2
votes
1answer
489 views

New Thermostat installed but compressor comes on immediately

I have a new Insteon Thermostat that I'm using to replace my prior Honeywell t-stat. This is installed to a relatively new HVAC system (both AC and Heat) that DOES have a "c" wire. I've attached the ...
0
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0answers
6 views

Manually Toggling Heatpump Reversing Valve to enable cooling

Background A Radiothermostat CT80 fails to signal heatpump cooling, so jumpering the RED node with the GRN (Fan) and YEL (Cooling) node has successfully enabled cooling. The weather became cold, ...
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0answers
6 views

Evaporator fan motor does not turn on, could it be thermostat?

If thermostat freezes, will it not turn on the fan motor? It will turn on if I spin it manually. Whirlpool fridge with freezer on the bottom.
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0answers
10 views

Thermostat frozen over

I have a whirlpool fridge, with freezer on the bottom drawer? Freezer part freezes, but does not throw cool air to fridge part. Took apart freezer to check fan motor, spin the fan blade manually and ...
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3answers
923 views

Boiler heating extra zones

Background: This is a new house, with a boiler system I'm not familiar with. Instead of zone valves, each zone has its own pump (4 zones). There is a fifth pump on the other side of the boiler. Not ...
2
votes
2answers
37 views

No C terminal on furnace to connect a wifi thermostat

I have an new Emerson thermostat and would like to connect a c wire so it always has power. I have an extra wire that's not being used, but I don't have a C wire terminal on my furnace. I'm wondering ...
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0answers
20 views

Hook up new thermostat

Top brown picture is my old thermostat white is the new one , do I have it wired correct? On out side unit we have replaced motor, fuses, compassator ,cc contactor ,relay . We have a heat pump. But ...
1
vote
1answer
25 views

Switching from a Mercury Switch Thermostat to a XT500C Thermostat

I only have a white, red, green and yellow wires, from my old thermostat. I see multiple Red wires... where does a single red wire go... to the R connection...
3
votes
2answers
63 views

Thermostat White-Rodgers 1F82-261 switches to stage 2 heat for no apparent reason

I am running a central heat system that uses a heat pump as stage 1 and a gas furnace as stage 2. The thermostat used is the White-Rodgers 1F82-261 which supports 2 stages of heat. When using regular ...
1
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1answer
31 views

Connecting Common Wire to Control Board

I have a heat pump and want to add a thermostat that requires a common wire. I have read through many threads that show how to add a wire but I already have a few extra in the bundle so its not so ...
1
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1answer
24 views

Honeywell WiFi thermostat install

My old honeywell thermostat did not have a C wire as it was ran on batteries. I did find a light blue wire when removing the old thermostat that was not being used. Looking at the furnace circuit ...
0
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0answers
17 views

No furnace fan in cooling mode while hooked to a fresh air damper controller

I added a fresh air damper and control, ( Soler Palau MD6-ES24VK) to my furnace (2006 York GY9S). The damper worked great in the winter but now that I am doing some cooling, I noticed that the outside ...
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2answers
47 views

Ecobee install with AC system disconnected

My house which was purchased from a bank (foreclosure) was originally wired with both central air and heater (forced air). But when the previous owner left, he took the air conditioning unit. The ...
0
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2answers
46 views

how to install thermostat

Im trying to install a new thermostat but the wires dont really line up (not sure what to do about the blue). Which wires should be connected to which? existing thermostat and the new wires next to ...
0
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2answers
62 views

How can I install a Honeywell Wifi RTH6580WF1001 thermostat in place of a Honeywell RTH2300b?

I have separate heating (hot water) and air handler (cooling System). The current thermostat I'm using is a Honeywell RTH2300B and the new one I want to install is a Honeywell Wifi RTH6580WF1001. The ...
1
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1answer
46 views

Central Heat Won't Turn On When I Raise the Temperature on Nest Thermostat

I'm sure my heater is working. It's 47 degrees outside, and I'm only a little cool inside. My Nest thermostat is set to 67 degrees. The screen on my app (which agrees with the thermostat) is shown ...
2
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1answer
117 views

Ecobee Smart Thermostat- Using Room Sensor as primary control

This is ultimately a fairly simple question about the Ecobee3 thermostat and the wireless room sensor functionality, but I'll explain my situation first. Twin home, 2 stories + finished below grade ...
3
votes
3answers
54 views

Is it wrong to install both a whole house humidifier and a whole house de-humidifier?

I live nearish Pittsburgh. Our summers can get pretty hot and humid and our winters can get pretty cold. We have been planning to get a whole house humidifier because the house gets really dry in ...
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4answers
95 views

Connect two thermostats in parallel

I saw a thread about connecting two thermostats in parallel. I could not add comment to that thread , so I put question here again. My tenants always shut off thermostat or reduce temp when they are ...
2
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2answers
61 views

what brand of thermostat is this

The cover is missing from this thermostat, so I don't what brand or model it is and I don't have the manual for it.
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1answer
28 views

How can I control my furnace fan from a secondary thermostat?

I have a WaterFurnace geothermal system with upper and lower level zones. I recently added an outdoor wood burner and my issue is that I want to use a secondary stat to run the furnace fan during the ...
2
votes
1answer
25 views

Furnace blower comes on full time when the thermostat is set to Auto

I have a Maytag furnace and the blower motor comes on right away when the thermostat is placed in auto and stays on when reaching the temperature set point and the heat goes off. I have replaced the ...
0
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3answers
80 views

Can I reverse my heating zone?

I have a three zone hot water boiler based heating system. The boiler is currently at one end of my ranch style house. The radiators appear to be directionless (no valves or anything). One of the ...
5
votes
1answer
323 views

Is it Code to support Class 2 (thermostat) wires using a gas line?

Related to this question. Our gas furnace, while quite functional, has some quirks in its installation. One of them is that the installers cut off the old (original to the house) thermostat wires at ...
1
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1answer
27 views

Aquatherm - thermostat is dead. What to check?

(Thermostat: White-Rodgers 1F80-51 Heating Unit is aquatherm, XUAQ22-2, this is a heat exchanger hanging off a hot water heater, and giving us forced air heat for a 500 sqft space. Unit and ...
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0answers
20 views

Thermostat Upgrade, furnace C-wire reading low voltage

OK so here is the scenario. Upgrading thermostat from dumb to smart (Ecobee). I've done 2 others in my house that required re-wiring so I have a good sense for what should be done but I'm stuck. My ...
0
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1answer
8 views

Use Sonoff thermostat TH10 in one room to control a Sonoff Basic in another room

For those who are experienced with the Sonoff devices, I need to check the temperature in my living room using a Sonoff thermostat TH10, and when the temperature is above a chosen threshold, I would ...
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1answer
31 views

What terminal to use on AC for C wire / nest dual transformer install

So i purchased a nest gen 3 and proceeded to install it. This is on a dual transformer system, separate boiler and AC system. The good news was i had a unused G wire on the Heat side that I was going ...
1
vote
1answer
376 views

Why might a central heating programmer no longer override a room thermostat?

My central heating and hot water is governed by a Danfoss FP715 Si. Using this I can set the time each day when the central heating and the hot water come on and off. When the central heating is on it ...
11
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5answers
2k views

Most cost effective thermostat setting: consistent temperature vs. lowest temperature possible

The problem: Our heating bills are about 25% higher than our average neighbors according to our bill, yet our temperature is always as low as we can stand it (mid 50's), we have excellent insulation ...