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Questions tagged [nest]

The Nest is a programmable, internet-enabled thermostat

4
votes
2answers
803 views

Why won't my thermostat control the HVAC anymore after trying to switch thermostats?

I bought a new Nest thermostat which is supposed to be compatible but needs a professional installation (advice that should have been heeded by non-professional electrician me). This is to replace an ...
4
votes
1answer
2k views

Why is my indoor A/C Blower randomly turning on and off only with Nest?

I recently purchased a Nest Thermostat (3rd Generation). My old thermostat was working perfectly. I wired Nest the Same exact wiring as the old thermostat which is : Y1 W1 G RH RC. With Nest, the ...
3
votes
2answers
705 views

How to add C-wire from Laars mini-term

Folks, I am having problems connecting my Nest thermostat to a boiler. Given Laars Mini-term JVS series with Temperature Control PCB Module (pictured below) When I short Com call and Heat call wires ...
3
votes
1answer
3k views

Why won't my Central Heating Boiler turn off with Nest thermostat installed?

I bought a second hand Nest Thermostat v1 (the European model with heatlink). I installed it and the Thermostat seems to work. The central heating boiler (Vaillant hrPRO CW3 VHR NL CW 3/3) seems to ...
3
votes
4answers
5k views

Is the Nest thermostat smart enough to turn itself on BEFORE you get home?

I'm wondering if in "Away" mode, is Nest smart enough to learn about when you come home, and kick on approximately 30-40 minutes BEFORE then? Or does it only kick on when it senses you've come home? ...
3
votes
1answer
758 views

How do I get the Nest Thermostat to warm up my house prior to arrival

I have a Nest Thermostat and live in the UK. I have a radiator based heating system. When I leave the house, some time later the Nest realises this and sets my house to Away. From this point onwards ...
3
votes
1answer
409 views

Will a 3rd Generation Nest thermostat correctly adjust the humidity base on outdoor conditions?

If I plug my whole house humidifier into a 3rd generation Nest, is it smart enough to track outdoor temperature and adjust indoor as needed to keep condensation off the inside of the windows?
3
votes
1answer
238 views

How should my third-generation Nest thermostat be connected?

I have an old Honeywell Q674 thermostat with mercury in the house we just moved into. I'm attempting to upgrade to the nest 3rd generation thermostat, however the wiring labels are VERY different. ...
2
votes
3answers
7k views

Do I have one or two 24V transformers in HVAC control circuit

I have two old thermostats (one for heating, the other for cooling) that I would like to replace with a single Nest E unit. I have central air and gas heating. Cooling thermostat has the following ...
2
votes
2answers
2k views

Nest Thermostat Wiring for Baseboard Heaters

I'm using a Nest Thermostat to power baseboard heaters (240VAC). I have 4 wires that I have access to: 2 wires: Red/Black from a transformer which outputs 24VAC 2 wires: 24VAC from a thermostat ...
2
votes
1answer
44 views

Upgrading from a two wire analog tstat to a Nest, need help

I am looking to upgrade from an old analog tstat to a Nest. My old stat had only two wires connected (R and W) but the wire bundle had three. So I tried connecting the green wire to C and then turned ...
2
votes
1answer
2k views

Nest, Blue Wire, W1 and W2

I just got a Nest E thermostat and I'm trying to hook it up. There is a blue wire that I had assumed was the "C" wire, but looking at the furnace, it doesn't look like that's the case, as the blue ...
2
votes
2answers
264 views

Nest E Thermostat Power

My thermostat is in the basement, connected to a Honeywell R845A to run a circulating pump for heat. I bought an Nest E for the main house and it works great. I want to replace the thermostat in the ...
2
votes
1answer
47 views

Connecting Common Wire from thermostat to Air Handler

My apartment has a central heating/cooling HVAC system consisting of a gas-fired hot water heater which feeds hot water to a First Co air handler for heating, and a rooftop compressor which feeds ...
2
votes
1answer
61 views

Nest thermostat to Kelvinator furnace

My old thermostat had 4 wires. I replaced with a Nest thermostat. At times the AC condenser is running but the furnace blower is not running. Found other with this and they said need to add common ...
2
votes
2answers
6k views

Nest Thermostat - Not cooling

First warm weather using my nest thermostat and now trying to use the central air. However, only the fan turns on and it doesn't actually cool no matter how long I run it. (It worked perfectly in the ...
2
votes
1answer
8k views

Furnace blower motor runs briefly then turns off

I have an Amana AMH80804BN with a Nest thermostat (wires Y,C,Rh,W,G) and a 3 ton AC. I have been having issues with the AC portion the furnace (heat) seems to work fine. The AC will start out the day ...
2
votes
2answers
908 views

Help wiring a Nest thermostat in an unusual situation

The attached picture shows my current wiring. Notice there are two thermostats. The top one (Carrier, with four conductors) controls hot air heating. The bottom one (with two conductors, old mercurty ...
2
votes
2answers
9k views

my furnace fan stays on even when at temperature

I recently installed a 2nd generation NEST thermostat. I'm not home very often, but I was paying particularly close attention to the furnace after installing this thermostat and I noticed that the ...
2
votes
0answers
25 views

I have 2 wire going into R, how should i connect to nest?

I'm installing a Nest thermostat: How do i connect the blue and red wire? Nest tech said i have two transformer.. do i split them into RH, and Rc?
2
votes
1answer
598 views

Can't get 3rd Gen Nest to power fan on Trane XR95 furnace

I have a Trane XR95 furnace and I replaced my original Honeywell Pro 4000 thermostat with a 3rd gen. Nest. I noticed, however, after installing the Nest that I can't get the fan to run on its own ...
2
votes
1answer
350 views

No power in r line after changed thermostat

I have a carrier furnace 2008, just changed my old thermostat to new nest thermostat, forgot to turn off the power. Now I have no power on my r line, checked short fuse still good, red light in front ...
2
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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
1answer
331 views

1 nest to control all vales on UFH manifold?

We are having an extension done and intend on having all underfloor heating in the new area. Currently we have a valiant combi boiler supplying the main house which has been T'd off with a valve for ...
1
vote
2answers
4k views

HVAC wiring for wifi thermostat installation (Ecobee) gas furnace + AC

I'm trying to determine whether I can install a wifi thermostat (Ecobee or possibly Nest) with my existing gas furnace (dual stage) and electric air conditioner, ideally using existing wiring but able ...
1
vote
1answer
84 views

Can I just extend this blue wire in furnace for Nest thermostat?

First time doing this, don't want to burn house down. The brown bundle is coming from thermostat, the white bundle I suspect is coming from A/C unit. Do I follow these steps? Find a scrap piece of 18 ...
1
vote
2answers
97 views

Need to identify a common wire on my old HVAC

For Nest Thermostat 3, I am trying to identify a common wire on my old HVAC. The diagram can be found on the link below:
1
vote
1answer
2k views

Gen 3 Nest not charging suddenly

I installed a nest thermostat a month ago. A very simple two wire install for a boiler. It worked fine without any issues for a month. This morning I went to adjust the temperature remotely and was ...
1
vote
2answers
279 views

Where is “C” wire on Honeywell 8043F1036

My home is 3 zones (2 hot water, 1 steam) and heated with oil. I added a Nest Thermostat E to one of the zones and while it does work without the 'C' wire, I would like to wire it anyways so my relay ...
1
vote
1answer
643 views

Smart thermostat for single-zone HVAC

I bought my first home (townhouse) I want to install a smart thermostat I have only one HVAC and the thermostat is located in the main floor. I have noticed that upstairs is hotter than the main ...
1
vote
1answer
53 views

What terminal to use on AC for C wire / nest dual transformer install

So i purchased a nest gen 3 and proceeded to install it. This is on a dual transformer system, separate boiler and AC system. The good news was i had a unused G wire on the Heat side that I was going ...
1
vote
1answer
99 views

How Do I Wire My Nest Hello Doorbell With A Plug In Transformer?

I wired up a nest hello doorbell to my existing chime. It rings fine but lacks enough power to operate properly. That’s ok, it was a little expected. Unfortunately, changing the old transformer is ...
1
vote
1answer
287 views

Adding Unused C-Wire for Nest Thermostat

I'm having an issue with my NEST thermostat short cycling my air handler fan while in running AC. This is a known issue, and the fix seems to be adding a common wire to the NEST. My thermostat is ...
1
vote
1answer
1k views

Add-A-Wire - COMMON / C Wire to a 3 Wire Thermostat

I am battling a Nest and losing at every turn. I have a 2 zone system and was able to install a Nest on the 1st floor by repurposing a wire as a COMMON wire. Unfortunately, the 2nd floor only has 3 ...
1
vote
1answer
546 views

How to set Nest Thermostat to control blower without heat

I have a Lennox G14Q3 propane furnace (forced air). I used the Nest/furnace setup last winter without any problems with just the W and R terminals. But, these summer days I would like to push air ...
1
vote
2answers
5k views

Separate boiler and AC, to which does C wire connect for Nest thermostat

I have installed a Nest thermostat into a system with hot water heat and separate a/c system each with its own transformer. To run a C wire to gain constant power, does the wire connect to the boiler,...
1
vote
1answer
112 views

What could be causing my Thermostat “R” wire to only be 8 VAC?

I am trying to install a Nest thermostat. It says Rh not powered. I checked with a meter and I get approx 8 VAC reading. What could be causing this? The furnace itself ain't pretty. Update:
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vote
1answer
294 views

How to hook up C wire to Crown air handler

Sorry for the newbie question, but I would like to hook up a C wire so that I can get a Nest, Ecobee, etc. My current thermostat is just a regular battery operated Honeywell and looking at the ...
1
vote
2answers
1k views

HVAC contactor sparks when AC kicks?

The HVAC and control board is a McQuay Mark IV. I'm not sure if I would like to try and fix this myself yet. Just trying to figure out the issue before deciding where to go. Here's the scenario: ...
1
vote
1answer
64 views

Central Heat Won't Turn On When I Raise the Temperature on Nest Thermostat

I'm sure my heater is working. It's 47 degrees outside, and I'm only a little cool inside. My Nest thermostat is set to 67 degrees. The screen on my app (which agrees with the thermostat) is shown ...
1
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0answers
110 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
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0answers
42 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
1answer
68 views

nest 2nd gen, no common wire/terminal in the fan coil unit

I'm trying to install an older nest in my condo but it immediately complains that there's no common wire attached (error e24). I opened up the fan coil in my condo and there is no specific terminal ...
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0answers
42 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
42 views

Honeywell Thermostat to Nest E Dehumidification

I am trying to replace my Honeywell Prestige IAQ thermostats. I noticed that my downstairs thermostat has a dehumidification option (upstairs shows no such option). I checked the wiring at the ...
1
vote
1answer
79 views

Which terminal should I connect it to for a “C” wire on an american standard AM4A0A30

I'm trying to connect a 3rd gen Nest thermostat. I have a 2 zoned heat and 1 zone AC. The zone with this thermostat has a boiler wired Rw, W1 and HVAC wired Rc, G, Y1. It's summer so I'm only using ...
1
vote
1answer
434 views

Is my Nest thermostat wired correctly?

I've been having issues like the heat pump not heating. Now that it's hot outside, my A/C isn't working. Can someone tell me if my Nest thermostat is even wired correctly? If it helps any, here is ...
1
vote
0answers
211 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
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0answers
1k views

Running Airwave/Fan schedule with Nest (With Fresh air intake HVAC)

I am trying to make sure I am understanding the research/studies behind using just the fan to help reduce energy to cool/heat home. Nest has the option to set a schedule to run the fan in home to ...