Stack Exchange Network

Stack Exchange network consists of 175 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers.

Visit Stack Exchange

Questions tagged [thermostat]

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

3
votes
0answers
46 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 (...
2
votes
0answers
34 views

Thermostat wiring for ac

I recently installed a nest thermostat for our AC system. Unfortunately I was short sighted and just assumed all the wires were the color I needed. Since installing the thermostat our system won’t ...
2
votes
0answers
19 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 ...
2
votes
0answers
123 views

C-wire on Weil-McLain CGA Series 2

I have an old thermostat with only 2 wires connected to my Weil-McLain CGA Series 2 boiler. I would like to replace it with a Nest thermostat. I need to add a C-Wire in order for it to work. Luckily, ...
2
votes
0answers
668 views

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 ...
2
votes
0answers
35 views

Need help disassembling Groehe shower thermostat

I have what I think is a Grohe 19624 Shower thermostat like this the one shown here: http://www.guillens.com/index.jsp?path=product&part=392046. It is leaking and I need to get it apart to ...
2
votes
0answers
1k views

Trane Weathertron Stat to Honeywell RTH2510

I have a Trane Weathertron thermostat thst I am replacing with a New Honeywell RTH2510. This is a heat pump with auxiliary electric heat. The wires on the Tran thermostat are. R, T, O, G, Y, B, X2 ...
2
votes
0answers
1k views

Is Nest 3rd Gen Thermostat compatible as a replacement for Honeywell TH3110D1008

I have an Ultra-Zone EWC-ST-2E controller unit for my gas AC unit at home (heating and cooling). It is set for two zones. Where the first zone has to be on (heating or cooling) in order to enable to ...
2
votes
0answers
104 views

Why are certain radiators hot during the night when the thermostat is very low?

We have a gas central heating system and we have set the thermostat to come on at different temperatures during the day. Generally between 7.00 and 22.00 it is set between 19 to 22 centigrade. From 22....
2
votes
0answers
1k views

Are w1 and w2 both energized during a second stage heat call from the thermostat?

Short version: does two-stage thermostat always close W1 circuit when it closes W2 circuit, or they might be closed independently? Long version: I have two-stage furnace, currently connected to older ...
1
vote
0answers
22 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,...
1
vote
0answers
31 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
vote
0answers
46 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 ...
1
vote
0answers
25 views

How can I install a Y wire for a Nest thermostat?

Installed a new Nest thermostat yesterday. My setup is a 4 wire system. Green, Blue, White, and red. I have central air and gas heat. They had the Blue wire "C" into the Y for the AC. Since the Nest ...
1
vote
0answers
115 views

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 ...
1
vote
0answers
45 views

Thermostat has two wires going into C terminal

Trying to help my dad install his new Nest thermostat - for some reason his thermostat has two wires going into the C terminal. I've searched and cannot find any other question about a setup like ...
1
vote
0answers
34 views

thermostat does not accept C wire connected to AC unit

I have three identical thermostats, model Radio Thermostat CT101. Two of them have C wires connected to the burner and work fine. The third one controls a heating zone and also central AC. It has R ...
1
vote
0answers
43 views

How can I use home automation with hot water heating radiators?

My apartment (in a condo building) is currently using stationary PTACs (using electricity and hot water), which I'm planning to replace with a split-level A/C system (for cooling) and hot water ...
1
vote
0answers
21 views

How to Run Fan Only with Thermostar Furnace With G Wire

I have a Thermostar Furnace that works great for Heating our home. We do not have AC and do not want that. But, we do want to be able to just run the fan without heat. The W and RH wires were ...
1
vote
0answers
262 views

Where should I connect my C wire on Goodman GMP075-3 Rev.B

I am trying to install an ecobee4 to replace a digital battery powered thermostat. I removed the existing thermostat and found that there was a spare blue wire that was wrapped around the others that ...
1
vote
0answers
389 views

How to wire a Taco zone valve controller with ecobee

I'm having an issue with wiring my Weil McLain gas boiler. It was wired up fine and working for a single zone. I added (2) 4 wire zone valves in. So I now have 2 zones, a Taco zone valve controller(...
1
vote
0answers
16 views

Do I need to replace the thermostat wiring leading to my boiler?

I have a boiler in an old building with four different apartments. There are two thermostats that call for heat from the boiler, and valves that direct the hot water to the respective part of the ...
1
vote
0answers
78 views

Changing AC Fan Motor/Capacitor with No Luck

Issues with a central AC unit: Turned it on and heard a buzzing sound, but the fan didn't start. Started by looking at the dual capacitor. We happen to have two identical units, so I tried the ...
1
vote
0answers
84 views

Correct wiring for Nest thermostat with dual HVAC system

Trying to wire up this new-fangled Nest Thermostat E (the cheapy edition) to my home HVAC system, but unsure of what to do. At the thermostat, I have G, W, Y, R, AND Rc wires, but the R and Rc wires ...
1
vote
0answers
29 views

Portable heat pump strange thermostat

I've got an Olimpia Splendid Ellisse HP portable heat pump with strange/incorrect thermostat readings. According to another thermometer the room temperature is currently 16.9C, the heat pump ...
1
vote
0answers
66 views

Is this line voltage thermostat sufficient?

I'm replacing a bad Aube line voltage thermostat for my electric baseboard heaters. I liked the model, so I purchased what I thought was the same one - however I missed a letter in the model. What I ...
1
vote
0answers
212 views

Nest + opentherm + zone valve

I have a Nest 3G, I'm now considering to change my boiler due to age-related issues. Can someone tell me if I can connect the Heat-Link to both zone-valve (on/off contacts) and boiler (OpenTherm). I ...
1
vote
0answers
56 views

Smart Thermostat (Nest, Honeywell or Ecobee) from KMC wiring?

I moved into a 1br condo recently and was looking to update the thermostat to Nest (or other Smart home thermostat). The current thermostat model is KMC and when I took off the casing, the wiring does ...
1
vote
0answers
42 views

furnace wont kick in

My furnace seems to work intermittently. overnight its seems to stop... i have checked the thermostat and it shows says it is heating. fan is on auto, but nothing coming out. when i turn heat to off, ...
1
vote
0answers
2k views

Nest thermostat - electrical buzzing/humming noise

I have recently installed two nest thermostats (the black gen 3, and white model E). The system is gas radiator heat wired to the model E via the usual Rh and W wires, and Rh, Rc, Y, G, W wired to the ...
1
vote
0answers
463 views

Voltage Drop between W1 and Rc wires

I recently converted from Oil to Gas. One of my zones is no longer working post conversion (it was working, then nothing worked, and then after they replaced a defective unit on the boiler it didn't ...
1
vote
0answers
356 views

3 wire heating system, has 3 unused wires with 16v, can any be used as a common wire?

I hopefully have a quick question. I am thinking of getting a Ecobee or Nest smart thermostat, but doing my checks/research before getting one for this house. I rent, so I can only do minimal changes. ...
1
vote
0answers
198 views

Thermostat for my furnace has no power during fan-off delay?

I have an older Tempstar 5000 furnace and a newish Honeywell wifi thermostat. The furnace works fine and the thermostat appears to be wired correctly (4 wires including C wire) but for some reason, ...
1
vote
0answers
84 views

B and Y wire connected to Y terminal?

Is it common to have the blue and yellow wire both connected to the Y terminal in the thermostat? I went under the house and looked at the HVAC unit and it looks like blue is connected to C out of the ...
1
vote
0answers
695 views

Installed new Sensi Thermostat, Everything Works Except No Cold Air

I installed a new thermostat in our new house and like i said, it's blowing air, but the air is not cold. Here's how it was set up when it was working: Here's what Sensi said to do on the app as I ...
1
vote
0answers
1k views

Controlling 110v swamp cooler(Mastercool) using Nest thermostat

Afer hearing many great things about Nest Thermostat, I decided to buy the 3rd Generation Nest thermostat. But after doing much research, I came to know that my MasterCool Swamp Cooler will not work ...
1
vote
0answers
9k views

'Wait' indicated on my Honeywell RTH7400 thermostat after 1 week vacation

New Homeowner (December) and I need help troubleshooting. Everything was peachy keen until I returned from a week vacation. A/C will not cool, but fan will turn on if I take it off of auto. "Wait" is ...
1
vote
0answers
506 views

Should I pull ethernet cable to my thermostat?

I'm going to be installing an ecobee3 smart thermostat, and need to pull some additional #18 thermostat wire. Since I'm going to be pulling cable anyway, and I have a box of cat 5e ethernet cable, ...
1
vote
0answers
170 views

Can I usefully control an electric baseboard heater in 1 room with the same thermostat as my central heat?

My house has a gas furnace and heat pump (and AC). Unfortunately, one bedroom does not have air ducts hooked up. Is there a way I could install a baseboard heater in that bedroom and have it ...
1
vote
0answers
77 views

What is this device connected to my HVAC unit?

I have this device connected to my HVAC unit in my apartment. I only have it in two of my rooms. In one of the other rooms I do not have this unit and was able to install an ecobee seamlessly. However,...
1
vote
0answers
324 views

Installing new thermostat without a C wire. Can I use my heater/R wire instead? Random 13V as well

I'm installing a thermostat, but I don't appear to have a C wire. My old thermostat had R/RH,Y,G,and W. It's an AC system that was setup before I got here. The actual AC unit is a long way away and ...
1
vote
0answers
53 views

Added load to thermostat circuit?

I have a couple Nest thermostats that I want to power when my boiler is powered off. My plan is to hook them up to a 24v transformer using the existing R/W wires (no C wire and I don't want to run ...
1
vote
0answers
577 views

Adding a C wire

I know this question has been asked multiple times and I'm going to try some of the methods I have read in other threads but wanted to ask this question since I didn't see anyone else's wired the way ...
1
vote
0answers
101 views

Thermostat replacement in a double wide

We have a new double wide and I want to replace the thermostat with a new programmable one. We took off the old one and it has 3 red wires, 2 yellow, 1 white and 1 green. I get the 2 red indicate a ...
1
vote
0answers
635 views

Honeywell WiFi thermostat newly installed--not working

I just replaced a 2 wire thermostat with a wifi one that required a c wire. There was an unused blue wire which I attached to the C connector on the transformer at the furnace. At the thermostat, the ...
1
vote
0answers
64 views

Possible of override 2 zones with one thermostat

I have a vacation home with 2 zone heating. In the winter, it would be nice to be able to have remote access to the thermostat and 'turn on the heat'. Normally when vacant the 2 zones will be set to ...
1
vote
0answers
7k views

My furnace has a C - common wire but air conditioner uses it - how to hook up smart thermostat?

I bought an ecobee3 smart thermostat which requires the C wire. At my furnace there is no circuit board but there was a diagram and I was able to locate the C - common wire, but it seems to be used ...
1
vote
0answers
44 views

How to connect 4 fan coils with one wall control thermostat?

I have 4 fan coils (Sabiana sk-22)and I want to connect them with one wall control thermostat. How can I do?
1
vote
0answers
60 views

Should I install a doorway fan or dehumidifier?

I have central air in a rancher (one floor), and the living room is on one end of the house. That room is on a slab, and has always been noticeably hotter in the summer and colder in the winter than ...
1
vote
0answers
544 views

Replaced Thermostat, Furnace worked for 1 cycle now blows cold

Hello I just replaced my old White-Rodgers thermostat because it just wasn't working consistently (sometimes it would turn on the furnace, but mostly it wouldn't). I swapped it with a White-Rodgers ...