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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.

2
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1answer
29 views

Do any home thermostats have an adjustable control range?

I am having trouble with AC and need to replace it soon ; so I have been listening to it cycle .I knew it only stayed on a short time but I just found it runs less the 2 minutes ; that is with ...
0
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0answers
12 views

Heat not kicking on

I live in an apartment with radiator baseboard heating and an old Honeywell round dial thermostat (no external switch). Heat has been working fine all winter. Weather has warmed up past few days- it'...
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3answers
861 views

How many wires should be in a new thermostat cable?

When roughing in thermostat wire, how many pair wire would you use to cover most thermostats? I'm asking because keep seeing questions about C wire and wifi.
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0answers
11 views

Installed Honeywell R8285A 1048 control center combined with a Honeywell PRO 8000 thermostat

to operate an inline duct fan on a long run to a new addition. Thermostat in the new addition activates fan when the thermostat is set to cooling perfectly. I can use it to manually turn on the fan. ...
0
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0answers
19 views

Where to install C wire?

I need to run new thermostat wire since I don't have a C wire to power my smart thermostat, but need some guidance on where to hook it up. I have five wires at my thermostat, two going back to my ...
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2answers
47 views

I have an unused C wire hooked up to thermostat and have no idea where to connect it to the furnace for power

I know this question gets asked all the time but I've spent hours staring at forums as well as my furnace and at this point I'm desperate. I just bought a nest thermostat that needs a C wire ...
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0answers
21 views

Weathertron Xl1200 to Nest Thermostat

We have a Trane Weathertron Xl1200 heating pump with the thermostat pictured below and are trying to replace it with our new Nest thermostat. Our old system has a variable speed air handler and we ...
1
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1answer
47 views

Remove switch that controls thermostat

I recently bought a condominium in a large building, built in 2005. It has a single thermostat, and the thermostat works fine. But right next to the thermostat, there is a switch. It looks like an ...
1
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1answer
18 views

Old furnace with extra wire, but no c terminal Janitrol, 19 year old furnace

I've searched multiple threads regarding this, but I didn't manage to find any that seemed to match my use case. My board doesnt have a C terminal, and it doesn't have the other terminals connect to ...
3
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0answers
41 views

Can I use this White Wire for a thermostat C wire?

An AC-only machine cools a storage facility: no heat. The 30 year old thermostat is to be replaced with a wifi thermostat, which requires a C-wire to power the electronics. There are 4 wires: Red (...
1
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1answer
21 views

Can I safely jumper between either G or Y and RC at thermostat panel to troubleshoot AC problem?

I'm trying to troubleshoot a non-functioning AC. The fan does not come on and there is no cool air/condenser does not run. My thermostat is a Braeburn. Three things I'd like to try for ...
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0answers
15 views

Ecobee 4 not recognizing PEK

I have four wires going to the thermostat. So I installed the PEK 5 wires out of the PEK to color matching terminals in the furnace block. Going into the PEK were the four wires from the thermostat, R,...
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0answers
26 views

AC unit not turning on

My A/C doesn't come on when I set the temperature on the Braeburn thermostat very low. Also, the recirculation fan doesn't come on when I set the thermostats fan setting to 'on', as though the indoor ...
1
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1answer
28 views

Furnace with no “C” connection

I have a mobile home furnace. This furnace only has a 4 wire connection terminal, G,W,R,Y. I also have a condensing unit outside with the 24 volt 2 wires coming to the furnace. I know I connect one to ...
1
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1answer
58 views

How to connect a new C wire

I have a 2 zone, single stage, heat only system with 2 wires running to each thermostat. I'm looking to install 2 Ecobee's; I have a second Honeywell AT72D1683 that I can install if needed and have ...
1
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1answer
24 views

Converting I+ I- thermostat to 'standard' wiring

I've been replacing my thermostats with the RadioThermostat CT50, which reports to my home-brew home control/alarm system. I have a 3-year old AireEase 4-ton unit in the shop that has a Comfort Sync ...
0
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3answers
60 views

Updating old Lennox thermostat - wiring confusion

I am trying to update my old Lennox thermostat to a Sensi smart thermostat. I checked the compatibility on the Sensi website and it appears to be a match except for this cluster of wires on the left ...
1
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1answer
31 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
53 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
34 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
27 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 ...
0
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0answers
7 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
7 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 ...
1
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1answer
30 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 ...
2
votes
2answers
50 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 ...
1
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2answers
31 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 ...
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0answers
18 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 ...
0
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2answers
53 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 ...
3
votes
3answers
55 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 ...
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.
2
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1answer
27 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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0answers
31 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 ...
1
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1answer
53 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 ...
0
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1answer
10 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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0answers
39 views

Controlling one FCU with two thermostats

I have a chilled water fan coil unit that will feed two areas, living and the bedroom. I want to control the FCU with two thermostats, one in the living and one in the bedroom, (preferably) in a ...
2
votes
0answers
18 views

Will the existing wiring work with the new thermostat?

I am looking to upgrade my line voltage thermostat from a Dimplex mechanical thermostat to a Honeywell digital thermostat. Both thermostat has 2 wires on its back. Would the new thermostat work if I ...
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 ...
0
votes
1answer
30 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 ...
0
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2answers
68 views

29 volts too much for a 24 volt thermostat?

I replaced a digital non-programmable thermostat with a programmable thermostat and the new thermostat keeps the house around 60-62 no matter what temperature I set. When I contacted the manufacturer,...
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1answer
75 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 ...
1
vote
1answer
26 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...
1
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1answer
31 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 ...
1
vote
1answer
52 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 ...
0
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0answers
19 views

CT80 Thermostat Wiring Diagram Selection

Which terminal should the brown wire be connected to the RadioThermostat CT80? The original thermostat was wired as depicted: The brown wire is connected to terminal E (not F). As I understand it: ...
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4answers
133 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 ...
0
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2answers
51 views

Electrical code and/or common sense requirements for thermostat wire

I want to install a Wi-Fi thermostat, but the existing thermostat wiring didn't have a common wire. The house was originally wired with two-conductor cable since it was a heat-only system, and then ...
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2answers
37 views

Do I have to turn off “everything” when replacing thermostats?

I am about to replace my two thermostats. There's a lot of switches on the "control panel" (litterally) for my heating system and I am not familiar with procedures and afraid to turn something off ...
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0answers
27 views

Are my new thermostats compatible with my system?

My two old Lux Pro PSP511LC are dying (LCD going out on both!) so I got two new thermostats from a friend he didn't need we both thought I could use. They are the Orbit Clear Comfort 83521 thermostat. ...
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1answer
64 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 ...