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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Understanding CFM with Armstrong ComfortSync and variable system
I recently had my home HVAC system replaced with a 4-ton communicating Armstrong system (variable-speed AC and blower, 2-stage furnace) with a ComfortSync A3 thermostat (a rebrand of the Lennox ...
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What is the correct way to wire a Relay In Box (or similar relay) that has low-voltage signal wires bundled with 120V wires?
It is my understanding that low-voltage wires can share a double-gang box with 120V wires, as long as they are isolated from each other by a permanent divider. I was looking at getting this relay to ...
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Ecobee 3 Lite / Fan Center for Fan Coil / Aquastat
I live in an ancient (1967) condo with a two-pipe system. Cold supply in the summer, hot supply in the winter.
There is no electronic changeover or even an automatic cutoff valve. The radiator coil ...
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Honeywell WiFi thermostat jumper loop separate ac and gas furnace
I need to validate my understanding for the installation of a WiFi thermostat that requires 24volt continuous power to operate in a constant state. I am DIYer who is computer literate.
Like a number ...
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2 wires, both hot, for 240v baseboard thermostat
I am replacing the thermostats in 3 separate apartments and have run into the same situation for all of them. Each thermostat controls 2 baseboard heaters. The old thermostats had 2 wires coming out ...
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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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How can I override the fan to have it run 24/7?
How can I override the fan ON 24/7? Can I do this by putting a jumper at the thermostat between R & G and leave it there without a problem?
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Wire going between O terminal and B terminal
I'm trying to figure out if the Nest Thermostat is compatible with our system using their online checker where you have to select what wires you have. I see that we have one orange wire that looks ...
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Can a Trane TWE042C150B1 be connected to a honeywell t9 smart thermostat?
I went to replace my old honeywell thermostat with an updated T9, but the new thermostat wouldn't even start up. Digging in, the 'C' connection was on the 'B' connection at the Trane. There is no 'C' ...
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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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How to add C wire to a very old 2-wire Lennox G16 Gas Furnace?
I recently bought a Sensi Thermostat with Wifi to replace my vintage one. I thought it would work with my 2-wire heat only system because it has batteries , but found out that using the Wifi feature ...
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Two transformers connected to boiler, no A/C
My HBSmith boiler honeywell circuit box has a 2-wire from transformer to the thermostat. Then there is another transformer on the ceiling that has conduit to the same circuit box, but different ...
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Adding C-Wire for Nest to Triple Aquastat Relay L8148J
Need some extra eyes and advice on how to add a common wire to our current boiler setup. We have a Triple Aquastat L8148E that has 2 wire that connect to our thermostat. Like many before me, I'm ...
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How should I connect my Nest thermostat to correct heating behavior?
I’m trying to fix our nest. For most of the winter, it blew heat if we turned on the ac. We didn’t have time to fix it so now I’m trying. I have photos of the thermostat and of the unit at the ac.
The ...
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Converting heat pump thermostat to honeywell t9
I'm almost confident in installing new Honeywell T9 thermostat but niggling doubt.
I have two simple heat pump systems, each with own thermostat.
The original honeywell thermostat TH1210DH wiring
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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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How do I wire a/c if furnace wiring compartment has no y terminal?
I have been trying to figure this out for more than a year. All was running until HVAC company came to replace 2 thermostats with nest and rewired 2 HVAC units (a front of house and a back of house ...
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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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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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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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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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Provide utility and gen power to thermostat
I have a smart thermostat installed that is getting 24v power direct from the heat pump control panel. The T-stat is also controlling a boiler that kicks on when the HP can't keep up in the winter.
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Where do I connect a C wire in an old Furnace?
I am hoping to be able to upgrade to a smart thermostat but unfortunately my furnace doesn't have the "easy" option with an obvious C terminal.
My furnace is OLD but it actually has the full 5 ...
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Thermostat connection and NEST compatibility question
We have this thermostat. It's no longer allowing the temperature to be adjusted. It will control the furnace on/off, it just won't allow the temperature to be adjusted. Date & time are still able ...
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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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Use one Ecobee thermostat to control three electric baseboard heaters with Aube RC840 relays?
We have a number of electric baseboard heaters in our house that I would like to smarten up. Eventually I intend to get rid of these baseboard heaters, and replace them with a better heating system, ...
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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:...
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Connection for C wire on Mastertrol Mark V zone control panel
I have spent hours searching the web for information on this 20+ year old zone control panel, which supports 3 zones of Heat and A/C.
The thermostat I'm replacing (on Zone 3) connects to T4/T5/T6 as ...
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Installing Nest From HoneyWell T8575D Condo 8-Wire thermostats
My condo apartment current has the HoneyWell T8575D installed and I want to switch to Nest. But I couldn't find which Nest port should the "Fan Common" line go into.
The wiring from the wall ...
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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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Wiring of a Vine TJ225 thermostat
How do i wire a TJ225 Vine thermostat? I have 2 red wires, a green, a white, and a blue wire. Red wires go to RH, and R, G goes to green, white to white, and the blue goes to Y on the old thermostat, ...
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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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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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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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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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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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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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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 ...
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Correct Wiring for Furnace Blower Motor
After getting my furnace blower motor replaced, it now runs only in the following scenarios:
Mode "Cool" Fan "Auto"
Mode "Cool" Fan "On"
Mode "Heat" ...
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Honeywell T6 PRO Z-Wave Thermostat (model th6320zw2003) exhibits very erratic behavior after battery replacement
Background:
My apartment complex installed Honeywell model th6320zw2003 thermostats in all units about six months or so ago, and it had been working well for all that time. The only issue was that ...
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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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Honeywell T6360 wiring from Hive
I’m wanting to swap my thermostat over from a Hive one to Honeywell. I’ve attached a photo of the current Hive wiring and the new thermostat.
Please can someone guide me on how to move the wiring over?...
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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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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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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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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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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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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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