Home Improvement Stack Exchange
Home Improvement 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.

A thermostat is a device used to control a larger system, based on temperatures. A thermostat typically acts like a temperature sensitive switch, either opening or closing based on the measured temperature.

One of the more common uses in the home, is to control an HVAC system.

1382 questions
115
votes
7 answers

How can I add a "C" wire to my thermostat?

So, the spiffy new wi-fi thermostats want power on the C wire from thermostat, but the old thermostat doesn't have a C wire at it. What's the easiest way to add the C wire/24 volt to the thermostat location?
Aaron
  • 6,491
  • 7
  • 40
  • 61
26
votes
1 answer

How do you trigger the HVAC with wiring only?

I have a HVAC that has the usually wiring C R G W Y Pinouts What wires do I need to connect to turn on Heating? What wires do I need to connect to turn on the A/C? Is there a risk of damaging any circuitry in doing this? Is there a way of finding…
Ashitakalax
  • 539
  • 2
  • 7
  • 12
25
votes
13 answers

Do smart or programmable thermostats actually save money?

I am looking at replacing all the thermostats in my house. I have hot water baseboard heat and forced air A/C. Each room's baseboard heat is controlled by a thermostat in that room. I tend to prefer simple mechanical interfaces to digital "smart"…
JoshuaD
  • 447
  • 5
  • 11
22
votes
4 answers

Why don't programmable thermostats automatically switch between "Cool" and "Heat"?

While I can set my house to be a particular temperature, I still have to manually switch it between "Heat" and "Cool" mode, and this seems to be true of every thermostat (programmable or not) that I've seen. Is there a reason for this?
Adam Robinson
  • 941
  • 5
  • 16
  • 26
19
votes
2 answers

Do I need to be legally qualified to install a Hive smart thermostat?

As a competent DIY'er, am I legally allowed to install Hive myself? The reason for the question is I have been asked to provide a cert as I'm selling the house. If not, can someone point me in the direction of where it legally states I can.
Alan
  • 191
  • 1
  • 3
16
votes
2 answers

How to remove wires from thermostat without screws

How do I remove the wires from thermostat without screws holding the wires or any apparent hole to push and loosen the wires. Picture below shows the wires:
Rafael Velásquez
  • 279
  • 2
  • 5
12
votes
7 answers

Can I add a wood burning stove to radiant heat boiler system?

We just moved into a house that was built in 1905 and got our first utility bill... it was almost $800. ( $600+ of it was gas, from boiler). We are aware of our energy usage habits (bring temp down at night, etc), our previous bills in other homes…
Alex
  • 121
  • 1
  • 3
12
votes
5 answers

Why is my Nest thermostat not working with A/C?

I installed Nest thermostat a few weeks ago, replacing an old Lux programmable thermostat (there was nothing wrong with it). I connected 4 wires (R,W,Y and G) to the Nest. But as soon as I'd connect the Y wire, the Nest would give me an E4 error…
mcaddu
  • 121
  • 1
  • 1
  • 5
12
votes
5 answers

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 throughout the house, we don't have drafty…
David
  • 223
  • 2
  • 7
9
votes
4 answers

Buying a programmable thermostat to replace a manual one: any considerations?

I'm about to look for a programmable thermostat to replace a manual one. There are already a couple of good questions on thermostat replacement that make the task seem pretty straightforward for anyone who's done a bit of wiring (which I have done).…
rsgoheen
  • 366
  • 1
  • 4
  • 13
8
votes
2 answers

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 shows the correct room temperature and the set point…
Doug
  • 403
  • 8
  • 16
7
votes
1 answer

On a thermostat, are "R" and "Rh" terminals the same thing?

I have an older thermostat controlling an old ass Trane furnace with A/C. It has an "R" terminal and an "Rc" terminal (they are jumpered - see photo). I see references to an "Rh" terminal online. Are "R" and "Rh" terminals the same thing? This…
AwesomePossum
  • 85
  • 1
  • 1
  • 6
7
votes
2 answers

Replace two-wire thermostat

I'm replacing an old mercury thermostat with a digital one. The new unit has 7-8 connections (labeled w1,wh,r1,rh,y,c, etc.) and a bunch of instructions about how to connect similarly labeled existing wires. But there are no instructions about how…
mgb
  • 1,615
  • 2
  • 14
  • 16
7
votes
7 answers

Should I use 12/2 or 12/3 to wire a 220V electric baseboard heater and thermostat?

When I bought my baseboard heaters, thermostats and 220V breakers I was advised to get 12/3 wire. When I attempted to install the heaters I found that the thermostats, heaters, and even breakers have connections for only 2 wires. I have since read…
Luke
  • 71
  • 1
  • 1
  • 2
7
votes
5 answers

Does a thermostat need to be connected to the fuse box? My builder says no?

I just purchased a home, and was in the process of replacing the thermostats with Nests. I flipped off all the circuits in the fuse box, and the thermostat on the first floor powered off. However, the thermostat on the second floor still had…
Adrian
  • 87
  • 1
  • 1
  • 2
1
2 3
…
92 93