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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Find replacement HVAC transformer
I want to replace this HVAC transformer but I don't know any of the specifications or ratings for the existing one. This is hooked up to the heater in my garage/shop and the heater fails to kick on ...
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Which breaker controls the HVAC unit?
I want to inspect the thermostat wiring in my apartment. It's an old White Rodgers so I have to turn off the breaker before removing the thermostat housing.
My apartment has an HVAC unit that looks ...
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Does the thermostat send a signal directly or indirectly to a variable speed compressor?
I am trying to understand how thermostats electrically modulate the compressor speed in a variable speed system.
My Radiothermostat sends 24V signal through the YELLOW wire to fire up the compressor ...
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Ecobee thermostat warning with heat pump
Has anyone experienced this on an ecobee thermostat:
Ecobee Auxiliary Heat Running Too Long
I have a heat pump in the house
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Zone 2 smart thermostat c wire voltage question
I upgraded my zone 1 and zone 2 t stats to smart units. Zone 1 works fine, I have 24-28v testing red to c wire at zone 2 when zone 1 is turned on, if zone 1 is not running, I have nothing at zone 2.
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Why does hooking voltmeter to two transformers show 0 voltage?
I have two 24VAC transformers. If I hook the voltmeter to contacts 1 & 2, or 3 & 4, it measures about 26 volts. If I connect it to 1&3 or 1&4, or 2&3 or 2&4, I get zero. I ...
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Where to buy replacement thermostat jumper U-shape wire [closed]
I have lost the U-shaped jumper wire used for my old thermostat installation. Now, I am trying to reinstall the old thermostat but I am missing the jumper. Although I could use some spare wire or ...
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Is there a solid-state version of this relay/transformer combo?
One-line summary: Is there a solid-state version of the White Rodgers 90-113 Fan Control Center (Transformer and Relay Combination)?
EDIT to answer question: The thermostat draws 0.146A (3.5VA / 24V).
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Programming a Honeywell Thermometer -- don't understand why heat is lower than cool?
I'm trying to program a Honeywell thermostat. In the instructions, it states:
I don't particularly understand why the heat setting has a lower number than the cool setting. My understanding (perhaps ...
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Thermostat resetting to wrong temperature
I have an Emerson programmable thermostat (seems to be similar to https://climate.emerson.com/documents/blue-universal-thermostat-istruction-sheet-en-4211880.pdf). I went through and programmed it ...
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24v Doorbell Transformer for Smart Thermostat
I have searched for this topic and the previous answers are not conclusive to me so I will try again with my specific situation. Thank you in advance for your help!
Current situation: I have a 16V ...
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Need help wiring Alexa smart thermostat
I have an 2002 unit Condo. I have installed Alexa smart thermostat. I replicated the exact wiring but thermostat only blowing hot air even when it says cooling is running.
Orange wire went to 'W' and ...
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Thermostat to control electrical baseboard heater
I wanna install 8 electrical baseboard heaters. So I need 3 circuits so I won’t over load them. So I wanna know if there’s a way to just install one thermostat
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What features or terminology do I need to look for in selecting a suitable climate control solution
Background:
We have a heat pump driven central heating system with four zones. Currently, the system operates as follows:
The heatpump heats a deposit of water
Water pumps, 4 in total, connected to ...
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Ecobee Thermostat / Common Maker / Gas Valve
I have a two-wire thermostat and an old forced air gas furnace in my house. When you open up the cabinet, inside you find a Dayton 2E228 Gas Valve and it is wired to an external 24VAC Transformer ...
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I'm trying to control heat remotely in a shop/garage that is subject to sub-freezing temps (which is OK with me when it is not in use)
I've learned that smart thermostats go into LO mode when temps drop below 35 and refuse to call for heat when in that mode. I've replaced the smart thermostat with a cheap mechanical thermostat that ...
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Problems with Honeywell T5 Thermostat Short-Cycling in Heat Mode
I have a Honeywell T5 WiFi Thermostat. I am running a gas furnace and an AC system that uses the furnace air handler. There are H, R, G and Y wires coming from the furnace. There was an unused 5th ...
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Furnace not working after installing nest thermostat [closed]
I installed nest thermostat without turning off power to furnace. Blower kicks on but not furnace. Is there anything I can do?
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How do I add a Google Nest Thermostat upstairs when I already have one downstairs?
I currently have a Google Nest Thermostat downstairs, and it works fine. I want to add a second thermostat upstairs and then have it 'learn' that I sleep upstairs so it should adjust the temperature ...
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How to add Thermostat C Wire to Furnace TH/TR and Transformer
I am trying to figure out the proper wiring for a C wire for my thermostat.
My 24v transformer and the current thermostat wiring at the furnace are shown in the pictures below.
Can I wire a thermostat ...
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I need assistance converting thermostats from a Honeywell RTH2300B1012 to Honeywell RTH5160D1003
I currently have a home with 3 zones and a central A/C and oil-fired forced hot air. The way the system has always worked in the main stat has to be set to heating or cooling for the others to run ...
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Replacing my thermostat: Do I have enough wires?
I have an old thermostat that powers my kerosene furnace in my mobile home. It also is powered by battery I believe. I noticed when taking the cover off there is only 4 wires and the previous owner ...
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Two electric baseboard thermostats on one circuit. The first box has six wires, the second just four (ignoring the grounds)
At the first thermostat is the group of two wires the line, and the group of three wires the load? The second thermostat along the circuit only has four wires. I put in a new thermostat on the second ...
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Heater Wire Connection
I just replaced my entire hvac unit and wiring and I wanted to add the Amazon smart thermostat. The ac works great. However, when I try to run the heater, it doesn’t shoot out hot air, only the fan ...
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What's the proper way for running thermostat wire along heating pipe?
I'm running new thermostat wire to my boiler (so I can get a c-wire to new thermostats). The old wiring runs along the heat pipe before it attaches to the zone valves. It used to be secured by wire, ...
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How to read wiring diagram of old zoning board
I'm trying to make a smart thermostat to work with my old zoning panel (20-ish years old?) in my house. The model is called MASTERTROL MINI-ZONE-3. It's mostly standard but with one quirk:
The Zone 1 ...
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What wire do I need to change and relocate my thermostat?
I ave a TRANE S9X2 Furnace-2 stage heat and Trane single stage XR 14 ac unit.I wanna move my thermostat and use new wire ...will 18 /6 do the job?
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Why doesn't my HVAC turn on with my new thermostat?
I am trying to replace an older Robertshaw with a Honeywell Home T5. The issue I'm running into is the home only has 3 wires leading to the thermostat: RH W G. The RH has a jumper to the RC. The new ...
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Installing single-pole thermostat for electric baseboard heat, possible short?
I am replacing an old 2-pole dial thermostat for 2 baseboard heaters with a new digital model (Honeywell RLV4305A). I was surprised that though it says it is rated for 220, it is only single pole and ...
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New Honeywell thermostat wifi install with 3 wire heat only [closed]
I have an old 3 wire set up at my current thermostat. Heat only. R - power, W - heat, G - fan. No additional wires to be used for C.
Instructions on the new Honeywell with wifi say that I can use the ...
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opentherm in parallel with on/off thermostat
I have a new Honeywell Lyric T6, in the living room, 20V 2-wired with the 230VAC control box near central heater. There is a parallel on/off thermostat, that kicks in if the house gets too cold when a ...
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What's the smallest tool-less splice for 18awg wire?
I've got a bunch of 18awg thermostat wires that need to be spliced in tight spaces. Normally I'd use wago lever nuts because they can easily be installed and removed by others, but at 8.2mm thick they'...
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Question about wiring for line voltage thermostat to control baseboard heater
I have a baseboard heater that is currently controlled by an end-cap thermostat on the unit itself. I removed the old baseboard heater and replaced it with a new one along with the thermostat cap. It ...
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Is it possible to replace a relay on a ncm300 zone controller?
I have an ncm300 zone controller which controls the 3 zones for my furnace and heat pump. There seems to be an issue with a relay sticking which is causing a continuous call for heat even when ...
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Oven is overheating... Are the components on the back burned up?
My oven suddenly started getting very hot even at low settings. This is a repeat event... 18 months ago it occurred and was fixed with a Controller board replacement. I'm hoping it's the thermostat or ...
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ecobee 3 lite: Controlling electric aux heat and oil heat as two separate stages
The problem:
I have an older hydronic system at home, powered by heating oil.
Recently, we've installed a heatpump with electric auxiliary heat. Meaning the heatpump will provide heat down to a ...
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What causes a 13 volt drop from 24v (read) red wire connection to from air handler to thermostat?
A voltage drop of 13 volts on the red thermostat "24v" wire. It reads 28v at air handler and 15v at the other, unconnected end. I was thinking a resisted short so I re-wired to an unused ...
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Honeywell T-10 fan will not stay on after cycle ends
I just installed a Honeywell T10 Thermostat to replace a Honeywell T5 that was professionally installed with a brand new HVAC unit four years ago.
The HVAC at this home is a bit unique in that it is ...
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Likely cause of heater being stuck on?
Our house has baseboard heat that is split in to about 10 zones (one per room). A few days ago, one room (the master bedroom) has been stuck on, making the room much too hot. The wall thermostat ...
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Will a Smart Thermostat Work with this Setup?
I currently have a thermostat with two wires: a C wire that powers the thermostat and an R wire that controls both the heater and central air. It's my understanding that smart thermostats won't work ...
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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 ...