Questions tagged [thermostat]
Mechanical or electrical device used to control a heating, ventilation, and air conditioning (HVAC) system, or other temperature reliant system.
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Only half of my apartment electric radiators come on
I hope I am in the right to place to ask for help.
I am in the UK, have a small apartment with 4 radiators. They look like they are electric (no pipes running to them). This is a relatively new build ...
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How do I know if the thermostat has a loose wire?
I am waiting for the technician to arrive in 48 hours but the thermostat seriously does not raise the temperature - it raises some but not much. It has been sitting at 61 half of the day while it is ...
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Issue with analog double pole thermostat for hydronic heating system which controls circulator pump and blower fan - Circulator and blower not synced
I just bought a house with a central boiler and circulating pump that provides hot water to hydronic heaters with blowers to each room. Each room has a MD26 thermostat which controls the circulator ...
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Why would a thermostat not be able to maintain temperature in an apartment with central water heating?
I live in an apartment with central water heating and a wall mounted Honeywell T822K1034 thermostat. I've had this thermostat before, and as far as I understand it works on the principles:
It has a ...
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Is it safe to cap and bury old thermostat wiring in wall?
We recently removed an old thermostat box and don't need it. There is a long brown thermostat wire now sticking out of the wall, so we want to cap it and push it back into the wall so we can patch and ...
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Thermostat two-wire: heat-only with R+Rh and O/B
Updated Dec 1, 2022 (Previously I wrongly believed that the boiler is connected to a heat pump, whereas it is actually connected to a temperature sensor installed under the heat pump)
I want to ...
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Can I use 16 amp rated smart thermostat on 30 amp circuit?
My 3 x cadet (King Electric PAW) forced air wall heaters (total of 3500 W) run off 240V 30 Amp circuit in my condo. My old line voltage thermostat from King Electric ESP-230 just broke and I want to ...
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How to splice three low-voltage cables
I am looking to interlock a new ERV to the existing air handler. The wiring diagram from the ERV manual is included below.
My question concerns how to splice together (is this the correct term for it?)...
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Solved: Y wire connected to C via a remote wall switch (not really)
In my new home I’m about to upgrade the thermostat. The unit is Honeywell AC plus gas furnace 2 in 1. New thermostat is a Honeywell as well. There’s no C wire in the wall, so instructions say: on the ...
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Thermostat does not reach desired temp
The thermostat was placed 9 months ago and the boiler was serviced at the same time. Anyway, I had the bedrooms temp held at 70 starting this morning and the maximum it got at 5 pm was 68. I turned ...
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Condo fan coil unit vent now blows on thermostat
I live in a 30 year old condo, and recently had the thermostat replaced on my fan coil heat/AC unit. Previously there was no thermostat, but simply an on/off switch with different fan speeds.
Here is ...
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Installing a Nest Thermostat
Installing on a boiler system: in-floor heat. No fan, air, or humidifier. I only have 3 wires. Red, blue, white. I was told I needed a common wire. My Honeywell programable thermostat (with batteries)...
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External furnace fan switch energizes AC
2010 house and thermostat. White Rogers 1F80-361 controlling a lennox furnace. We have a fan switch located above our Tstat that will turn the furnace blower on and will also energize a make up air ...
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wiring help for electric baseboard thermostat
The markings on the thermostat say "LINE RED" and "LOAD BLACK". Does that mean one red wire on the thermostat goes to hot white in the box and the other red wire on the thermostat ...
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How does an air conditioner remote control work with multiple AC units?
The apartment I rent has multiple Toshiba AC units used for both cooling and heating. I'm sometimes annoyed at how they sometimes seem to work weirdly - heating the room to absurdly warm despite me ...
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Swap Honeywell Mechanical swap to iolloi wifi thermostat
Ive tried swapping out a Honeywell mechanical T6360 for this Iolloi wifi (alexa compatible) cheap thermostat. However when I wired the mains (UK) N and L to the appropriate terminals nothing happened ...
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Replacing thermostats for in-floor heating
My parents' house has a two-zone, in-floor hot water heating system, currently controlled by two separate Honeywell Chronotherm III thermostats. One of the thermostats is non-functional as the wires ...
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How to wire in-duct heat strip to geothermal unit with nest thermostat
I have installed a new in-duct heat strip for my geothermal heat pump.
Heat strip: Warren SL20A Electric Duct Heater
Heat pump furnace: GeoCool 5 Ton
Thermostat: Google Nest 3rd Gen
My situation is I ...
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Why won't my Vaillant thermostat's remote control pair with the base unit?
A couple of months ago I installed a brand new Vaillant room thermostat (VRT 350f) for my quite old Vaillant boiler (ecoTEC plus 937). It was a breeze to install and did its job perfectly until ...
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Overlapping HVAC
I had about a 1,500sq ft single level ranch style home. A few years ago I added on a master suite and a family room, so now about 2100sqft.
The family room has a large pass-through to the rest of the ...
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Smart thermostat with external transformer
I have separate heat and cooling systems with wiring to Y, W, G, Rh and Rc. I don't have a C wire and therefore I will be using an external 24 V transformer. For the external transformer, where do I ...
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How is this working? There is no W,Y,G wires?
Single stage gas furnace and ac w Honeywell thermostat w no W,Y, nor G. How would this work? I’m trying to convert to nest.
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What setting for thermostatic radiator valves when leaving a house at low heat for the winter?
We just bought a new house (new to us, it was built in 1960 and unrenovated) and only have a few days before we leave it for November/December. We are planning to leave the heat on with the ...
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How to connect thermostat to this furnace?
I have an oil burning Brock EliteAir furnace, it has 2 wires Tw and Tr on the burner section going to the thermostat. BUT there are C Y G R wires on the side ( where there's a fan logo) that are not ...
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Hooking up new line volt thermostat for elec baseboard
Trying to install a new thermostat to electric baseboard heating.
Heating is 240 V, new thermostat is Honeywell RLV3150
Current dial thermostat is hooked up, and the junction box has 3 wires going to ...
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Is there a smart thermostat that can be set to turn on at a temperature, and heat to a moderately higher/lower temperature?
In the winter I'd like to only run the heat occasionally. Ideally I'd like to keep the temp somewhere between 68 degrees and 74 degrees (F). Ideally when the temperature drops to 67 the thermostat ...
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Missing c wire for new thermostat
Tying to install new smart thermostat but no c wire available. Was going to use g wire in c terminal but noticed the the g wire( old thermostat) is green and when I checked furnace,that green wire is ...
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Where to add C wire?
Would anyone be able to tell me which group of wires I add the C wire too?.
I think it’s the white one but want to make sure
Thank You
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Smart Thermostat - C Wire
I'm about to go out and buy a smart thermostat for my place and had a question about the 'c' wire (common wire). From what I've read online, the blue wire is commonly known to be the c wire for the ...
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How to fix/calibrate mechanical thermostat that sometimes won't turn on heater?
In my house I have mechanical thermostats that control wall-mounted electric heaters. I have a couple of problems with these thermostats:
Sometimes they won't turn the heater on at all. Even if I put ...
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AC blowing hot air
I have been remodeling a small building for the last 6 months or so. We had power disconnected to this building since April. We just barely got the power back on, and after some work were able to get ...
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Adding a C wire to Nest learning thermostat 3rd gen
I'm trying to add a C wire to my Nest thermostat, I already had the C cable on both ends but it wasn't connected, I went to the attic and connected the blue wire from the thermostat wiring to the C ...
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Adjust Multi-Speed Carrier Furnace via thermostat as in manual, or need to rewire?
I have a Carrier 59SC2C100S211120 furnace. The blower is pretty loud and everyone says they really feel it when it comes on. I would like to turn down the blower in normal operation and then, if also ...
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Oven thermostat substitute?
I own an oven that uses a 2168 thermostat pictured here:
with a wiring diagram that looks like the one on the right:
. For reasons that I can't determine (mercury?), this thermostat is very hard or ...
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HVAC Thermostat not powering on, blown transformer?
We have recently been having some remodeling done at a currently not-occupied home. One of the things done was a brand new breaker was installed. Before the breaker was installed, our HVAC was working,...
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I'm installing a nest thermostat. The wires at the base are R G Y W
On my 24v transformer there is a C POST. I have wired the nest thermostat with the 4 wires R Y W G. Nest says the termostat needs a c wire,Can I just run a wire from the C post on the transformer to ...
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Turning HVAC on/off using the circuit breaker
So my thermostat is fried. Had a very capable HVAC technician take a look at it and he found this out. I have ordered a new one but it isn't going to be here for the next 2-3 days. I live in Texas and ...
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Heat Pump Condensate Safety Switch Wiring Question
I recently purchased a simple condensate overflow safety switch (Rectorseal 97647) to install in my attic air handler unit. I currently have the switch installed on the red wire, but do notice the ...
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Furnace/thermostat wiring confusion
[We purchased a house last year and I am just now getting around to this. We are wanting to exchange our non programmable thermostat T6-NHP01-A to a programmable one (we have a nest). I have changed ...
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Help on Wifi Thermostat Wiring Guide
I do have the WiFi thermostat (picture attached) that I m trying to attached with my current central airconditioning unit but no success after trying multiple wiring. I does have three wires coming to ...
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Can you install a heat pump with 4 wires?
I currently have a central AC system. I'm looking into replacing it with a variable speed one. I've been told that if I'm replacing it anyways, I should look into getting a heat pump instead for a ...
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What would cause the fan setting on my thermostat not to turn on the air handler fan
Just recently the fan setting on my Honeywell RTH8500D doesn't turn on the air handler. This is a recent problem. I usually run the air handler 24/7 during "pollen season" to filter the ...
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New thermostat not compatible?
I have a new Honeywell thermostat that says it is compatible with oil furnaces, but I just took off the old rotary one and it appears there are only two black wires. I assume this will not work, ...
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replace fossil-fuel kit on dual-fuel heat pump with upgraded thermostat
I have a 25-year old dual-fuel heat pump (about which I've asked many questions here). There is a PCB in the furnace/air-handler called a "fossil-fuel kit" that handles switching between ...
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No voltage on old thermostat wiring
I'm trying to add an amazon smart thermostat. I don't have a C wire, but there is a spare black wire behind the thermostat. I put my multimeter on 200 VAC and expected to see 24 VAC on the red wire. I'...
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240 volt to 120 volt plug from HVAC blower motor
I am trying to place both germicidal lamps (approx 70 watts total) and a negative ion generator in my air condition return space where the blower motor is.
My fist advice was to run these two devices ...
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why does my air conditioner run when at set point
my 10 year old a/c now starts even though house is at set point. if I raise set point it will shut down. all day long with set point at 79 it will start, run and shut down again with ambient temp ...
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C-Wire Adapter without Y wire on board
I was looking to get our AC thermostat replaced with a smart one. We have an outside unit, upper unit, and the thermostat. I checked it out and no surprise, there was no C-Wire in use or hidden ...
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What should connect to the COM contact on my new thermostat?
I am replacing a fan-coil thermostat. Unit itself is Wito ultra-s 06-2t. Old one was wired and installed by an electrician, quite some time ago. I dismounted the old one and wanted to replace it with ...
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Can it happen that with a high hot water output in an electric dual flip-flop thermostat heater the lower thermostat is never turned on?
We have a problem with an electric dual element heater with flip-flop thermostats (only upper element working).
The plumber changed both thermostats once, the heater failed again in the same way, and ...
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