Anyone know how to install a new thermostat panel?

Khraul · January 2017

Hey everyone!

SO... I picked up a new thermostat today because apparently we needed a new one (the old one is ugly and we're repainting the house, as I was told by my S/O), and based on what I have for heating and cooling the guy at the HVAC place said the new Honeywell he sold me would cover what I needed. I figured it'd be a simple case of swapping wires over, but the wiring labels on the old Sears brand thermostat doesn't match the new one. I have a 2H/1C system, with a gas furnace, and an AC unit with built in heat-pump.

There are two cables coming out of the wall that split into six wires. One that's black and white, and another that's black/white, white, red and green (respectively these are wired to the old thermostat as W2|R and C|Y|"O/B"|G)

I've checked the manual on the new one, and it indicates the following:
W= Heating
Y= Cooling
G= Fan
O/B= Changeover

C, R, R2 aren't listed in the manual. And I can't find a manual for the old model to tell me what the letter designations mean (I can't even find one online... it's a Sears C387).

Now I know how to install and fix a lot of stuff, electronic and mechanical, but I know absolutely ZERO about heating and cooling systems. The two pictures below are the old thermostat wired up and the new one unwired. The new one also came with a little silver jumper between R/RC.

Anyone know what the heck I'm supposed to do here, or if I was sold the wrong type/model of panel?

Thanks in advance for any help!

Cambiata · January 2017

Just from the visual alone, you can see on the wired example there are letters next to each screw that has a wire in it - I see Y, G, R, and C that match up to letters on your new thermostat. There are two wires that do not match up, E and... O? maybe AB? I can't see the letters because the wire is in the way. When I plugged in my new thermostat, there were instructions to tell you were the "old" wires hook up into the new device, so you should have some instruction manual (potentially one you have to look up online) to tell you where the non-matching letter wires go.

Did further research and it seems that the letters I can't see might be O/B. That wire actually appears to have a spot in the new thermostat marked with the same letters, if that is O/B. I would look at whatever instructions came with your thermostat for the 'E.'

mRahmani · January 2017

I wired up one of these last year, and it took some trial and error to get it all going. There should definitely be some instructions with the new unit on what the old unit equivalents should be.

Khraul · January 2017

I feel like I'm missing a manual page... it seems like I should have a page like you both mention with wire descriptions.

The manual doesn't even have descriptions for all the wires on the NEW thermostat...

Cambiata · January 2017

Khraul wrote: »

I feel like I'm missing a manual page... it seems like I should have a page like you both mention with wire descriptions.

The manual doesn't even have descriptions for all the wires on the NEW thermostat...

I went to the honeywell URL that's printed on your new thermostat and found this, any help?

http://yourhome.honeywell.com/en/general-pages/wi-fi-programmable-thermostat-home-compatibility

bowen · January 2017

E is emergency heat, looks like the new thermostat doesn't support it?

R is 24v AC power

R, Rc, Rh should all be the same thing. Sometimes you need a jumper between them depending on the system (so the thermostat knows how to turn on Rc).

Does your furnace have 2 stage heating? W2 is the "high heat" on gas furnaces, and E is sometimes "normal heating" or "low heating". But that's entirely dependent on you having a heat pump. Which it looks like you might have. I don't know if the new thermostat will work, or work properly/efficiently.

Khraul · January 2017

Whelp... I figured out the problem. My furnace is gone.

After dicking around with the furnace, checking the fuse, and doing some diagnostics, I reinstalled the old thermostat panel and just tried to run the furnace without the heat pump because I suspected that I had the wrong replacement panel and that something else was up.

I've learned two things after talking to the heating guy that I had in today... 1) I was sold the wrong thermostat... I didn't have the wiring terminals in the new panel to connect a heatpump. 2) The only thing keeping my furnace from having serious problems (like fire damage problems) is a snap-switch that turns the whole furnace off when it overheats because the heat exchanger is borked and is shooting flame out of the backflow on one side instead of up into the space where it's supposed to go and heat air.

This explains why my heating system hasn't been working properly. :bigfrown:

Thank you very much everyone for the help and suggestions. I have a new furnace being installed friday.

bowen · January 2017

If you've got the money, get a Nest thermostat when you get a new furnace. They are amazing.

iRevert · January 2017

bowen wrote: »

If you've got the money, get a Nest thermostat when you get a new furnace. They are amazing.

YMMV

Every Nest that I've tried (3x) and all the ones friends have tried have come with oodles of issues and have failed within a short period of time.

EDIT:

In addition NEST thermos don't work for every type of setup so you need to really check into that before you purchase to avoid a repeat.

bowen · January 2017

Judging by at least the current setup, it should work.

Mine's working fine, so, I guess we'll see.

iRevert · January 2017

bowen wrote: »

Judging by at least the current setup, it should work.

Mine's working fine, so, I guess we'll see.

In the past they haven't played well with Trane products, I don't know if they ever fixed that but he should check into that if he considers a Nest.

EDIT:

I should clarify that I live in a true "winter" area where if your furnace fails for an extended period of time pipes will burst and you're in for a world of hurt. When poor firmware updates are pushed that cause the thermostat to fail for whatever reason or if it loses wifi and decides to throw a fit and no longer work with the temps it was told it is a very very bad issue if you travel. As I said YMMV so do some research on them and see if they fixed those issues.

VishNub · January 2017

We have a Sensi, which is sort of a cheaper non-learning nest. It's programmable and wifi controllable, and it's main thing is that works with nearly all hvac setups. I like it, even though I didn't want to.

bowen · January 2017

I live in a true winter area too.

Khraul · January 2017

I don't anymore... I used to live on the ND/Manitoba border (Canadian side) and heating was a super big priority.

Now I live outside Vancouver BC... it's less of a concern.

Figgy · January 2017

FYI next time, just pop the panel on your furnace to see where each coloured wire is connected to on the panel. Then, connect that wire to the right part on the thermostat. Sometimes they're just capped and not used (like a boiler wire or dehumidifier, for example).

Khraul · January 2017

Figgy wrote: »

FYI next time, just pop the panel on your furnace to see where each coloured wire is connected to on the panel. Then, connect that wire to the right part on the thermostat. Sometimes they're just capped and not used (like a boiler wire or dehumidifier, for example).

That's another problem I ran into... at some point when the heat pump was added after the furnace new wiring was run... the furnace panel was accurate to the wiring diagrams I'd found color wise, but they didn't match the wiring upstairs where the panel was.

It was just a problem all the way around

Figgy · January 2017

Khraul wrote: »

Figgy wrote: »

FYI next time, just pop the panel on your furnace to see where each coloured wire is connected to on the panel. Then, connect that wire to the right part on the thermostat. Sometimes they're just capped and not used (like a boiler wire or dehumidifier, for example).

That's another problem I ran into... at some point when the heat pump was added after the furnace new wiring was run... the furnace panel was accurate to the wiring diagrams I'd found color wise, but they didn't match the wiring upstairs where the panel was.

It was just a problem all the way around

That's not really possible. All those little wires are in the same casing and it just runs right up to your panel, no? Not familiar with heat pumps; does the furnace run to the pump and then up to the panel?

iRevert · January 2017

Figgy wrote: »

Khraul wrote: »

Figgy wrote: »

FYI next time, just pop the panel on your furnace to see where each coloured wire is connected to on the panel. Then, connect that wire to the right part on the thermostat. Sometimes they're just capped and not used (like a boiler wire or dehumidifier, for example).

That's another problem I ran into... at some point when the heat pump was added after the furnace new wiring was run... the furnace panel was accurate to the wiring diagrams I'd found color wise, but they didn't match the wiring upstairs where the panel was.

It was just a problem all the way around

That's not really possible. All those little wires are in the same casing and it just runs right up to your panel, no? Not familiar with heat pumps; does the furnace run to the pump and then up to the panel?

Some homegamer doing the wiring and runs short on a couple of wires so they splice in whatever is handy thus making weird colors come out. I've seen old electrical wiring where they spliced the wires in backwards so it was the opposite at the box and at the junction.

bowen · January 2017

And if you're lucky, that's the worst of what you find.

Khraul · January 2017

That was the case here... The furnace wasn't originally set up to run a heat pump, so when the heat pump was installed they ran new wiring from the furnace, to a panel strapped to the furnace that runs the heat pump, then up to where the thermostat was... The wiring they used that should have been orange and blue ended up being black and white just like the original black-and-white that runs from the furnace. So instead of blue / red / green / orange / black / white, I ended up with red / green / 2 black / 2 White.

Jasconius · January 2017

VishNub wrote: »

We have a Sensi, which is sort of a cheaper non-learning nest.

that's ok, Nests don't really learn either 8-)

i've had a nest for about two years, and I've only had one technical problem with it ever (global firmware glitch)

however the learning part of that device is pretty much a crock of shit. i can never get mine to adapt to new behaviors in any reasonable period of time. so i end up just using the app to reprogram it manually, there are no settings as far as I can tell that make it more sensitive to your behavior...

also, as far as energy savings are concerned, I gotta be honest, I really just can't see what it's REALLY doing that any other decent thermostat can't do either

all in all i would say apart from the fact that it looks cool, is easy to install and use, its value is questionable

bowen · January 2017

Jasconius wrote: »

VishNub wrote: »

We have a Sensi, which is sort of a cheaper non-learning nest.

that's ok, Nests don't really learn either 8-)

i've had a nest for about two years, and I've only had one technical problem with it ever (global firmware glitch)

however the learning part of that device is pretty much a crock of shit. i can never get mine to adapt to new behaviors in any reasonable period of time. so i end up just using the app to reprogram it manually, there are no settings as far as I can tell that make it more sensitive to your behavior...

also, as far as energy savings are concerned, I gotta be honest, I really just can't see what it's REALLY doing that any other decent thermostat can't do either

all in all i would say apart from the fact that it looks cool, is easy to install and use, its value is questionable

The best part is the scheduling tbh. Being able to adjust it and scale it up and down through the day and weekend is nice. Normal programmable thermostats are garbage and are stupidly difficult to program anyways.

VishNub · January 2017

bowen wrote: »

Jasconius wrote: »

VishNub wrote: »

We have a Sensi, which is sort of a cheaper non-learning nest.

that's ok, Nests don't really learn either 8-)

i've had a nest for about two years, and I've only had one technical problem with it ever (global firmware glitch)

however the learning part of that device is pretty much a crock of shit. i can never get mine to adapt to new behaviors in any reasonable period of time. so i end up just using the app to reprogram it manually, there are no settings as far as I can tell that make it more sensitive to your behavior...

also, as far as energy savings are concerned, I gotta be honest, I really just can't see what it's REALLY doing that any other decent thermostat can't do either

all in all i would say apart from the fact that it looks cool, is easy to install and use, its value is questionable

The best part is the scheduling tbh. Being able to adjust it and scale it up and down through the day and weekend is nice. Normal programmable thermostats are garbage and are stupidly difficult to program anyways.

The Sensi is fairly easy to install and program via the associated app. I didn't and don't care about the wireless/online aspect of it, other than 1) if you go on a trip you can turn the thing off if you forget and 2) one time the power went out in the middle of summer for two days, so we went to stay somewhere else and I could tell when the power came back on by seeing the thermostat working.

Pailryder · January 2017

putting in a recommendation for EcoBee https://www.ecobee.com/
We've had ours a couple of months and love it. All of the smart thermostats have similar features with different pieces being more important to different people. What i like about the ecobee is the remote sensors you can put in various parts of your living spaces. Also, in the State i live in, the gas company gave me a credit for purchasing a smart device, you may want to check into that if in the USA. Also, also, the ecobee was by far the easiest home appliance i had to install, their app walked me through everything with pictures, videos, text, everything. It had me take a picture of my current setup and figured out what wiring i had and how to wire up the new device.

bowen · January 2017

Yeah my power/gas company gave me a huge discount on the NEST.

I got like $100 off.

azith28 · February 2017

You could also just trace the wires back. color should stay consistant from the heater/AC so just check whats coming out of the wall to what device vs your thermostat wires.

bowen · February 2017

not always!

BlazeFire · February 2017

Khraul wrote: »

That was the case here... The furnace wasn't originally set up to run a heat pump, so when the heat pump was installed they ran new wiring from the furnace, to a panel strapped to the furnace that runs the heat pump, then up to where the thermostat was... The wiring they used that should have been orange and blue ended up being black and white just like the original black-and-white that runs from the furnace. So instead of blue / red / green / orange / black / white, I ended up with red / green / 2 black / 2 White.

azith28 wrote: »

You could also just trace the wires back. color should stay consistant from the heater/AC so just check whats coming out of the wall to what device vs your thermostat wires.

DIYers be crazy.

Foomy · February 2017

BlazeFire wrote: »

Khraul wrote: »

That was the case here... The furnace wasn't originally set up to run a heat pump, so when the heat pump was installed they ran new wiring from the furnace, to a panel strapped to the furnace that runs the heat pump, then up to where the thermostat was... The wiring they used that should have been orange and blue ended up being black and white just like the original black-and-white that runs from the furnace. So instead of blue / red / green / orange / black / white, I ended up with red / green / 2 black / 2 White.

azith28 wrote: »

You could also just trace the wires back. color should stay consistant from the heater/AC so just check whats coming out of the wall to what device vs your thermostat wires.

DIYers be crazy.

Pro's are also just as lazy, if they run out of the right colour wire but have some other sitting next to them you better believe they will use that than have to go out to the truck to get the right stuff.

bowen · February 2017

if it's a case where the walls aren't even in yet, they sometimes splice if they're a really shitty person

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