How difficult is it to replace a themostat?

[yesthattom]

I have a non-programmable thermostat, and adjusting it twice a day is becoming a pain. (and even with adjustments, we paid $400 in gas last month). I found what looks like a reasonable replacement but the installation instructions include a lot of details about connecting wires, etc.

• If you’ve replaced one recently, how difficult is it?
• Does the model above look good? Can people recommend a better unit?

Feedback is appreciated.

Comments

[kimuchi.livejournal.com]

I've done it, it was a piece of cake. You might have more controls available to yours than I did (it was a rental house with heat only -- no fan, no A/C, etc.), but it still shouldn't be too hard.

[yesthattom.livejournal.com]

Mine is only going to control a gas furnace. No central A/C or anything fancy like that.

My concern is that the wires will be unlabeled and difficult to deduce which is which.

[sweh.livejournal.com]

Use a voltmeter to measure the voltage on the wires to your existing controller. If there are only 2 and it's around 24V AC then it'll work just fine. Check carefully if there are any labels on your existing controller; if there are then they might be standard labelling and so will tell you what terminals of the new unit to use.

[docstrange.livejournal.com]

It's pretty easy to do. I've done replacements at two of the places I've rented over the years. The wiring is all modest voltage, and doesn't present a risk. It's just 2 or 3 wires, and if you're careful to note what is connected to what before disconnecting the old one, you'll be fine. The one recommendation I can make from experience is - unless you like doing wall work - get one that's as close in size to your old one as possible. Many state what old models/types they replace.

The one you link to seems total overkill for replacing an old analog one - most of the things it can do probably don't even have wiring going to the old one.

[yesthattom.livejournal.com]

Good point. I bet I can find one that is a lot less expensive that just controls heaters.

[snowboardjoe.livejournal.com]

Part of the cost is in the programming functions. Definitely shop around, but you may find that there are no heat-only, programmable thermostats.

[kimuchi.livejournal.com]

There are heat-only programmable thermostats, the one I put in was like that. It was a basic Lux brand model from Home Depot. The UI left something to be desired, but that's to be expected with these things I think.

[snowboardjoe.livejournal.com]

Yeah, I think the UI on any of these devices generally suck. Fortunately the whole idea with these things is to set it and forget it!

Actually, the one I have is made by Hunter and it does make it very easy to make temporary adjustments.

[snowboardjoe.livejournal.com]

You can do it and this thermostat looks fine. A noobie could probably knock out this job in 15 minutes. If you're still not sure, post some pictures.

There is a semi-standard for wire coloring, but never a guarantee. The instructions will be complicated as they are trying to address a broad variety of systems (heat pump, furnace, fan control, AC, etc.). The wires you will need to hook-up will be minimum. DO carefully mark how the wires are currently attached to the old thermostat. That could provide all the info you need to hook-up the new one.

Just turn off the furnace to prevent from getting zapped. 24V is not life threatening, but you don't want to short something and cause other problems in the system.

[slinkr.livejournal.com]

Have you checked with your gas company and/or electric company to see if they offer any deals on programmable thermostats? They might even do the installation for you.

[mhalligan.livejournal.com]

I've installed them for simple electrical based units, and it was just two wires. Do you have the manual for your furnace?

[vees.livejournal.com]

I highly recommend the Rite Temp 8085C. I bought it because:

1. The display numbers are huge.
2. Its a touch pad interface.
3. It was reasonably cheap.
4. It has a humidistat.
5. It's indiglo backlit.
6. It has a temperature swing adjustment, so you can trigger it to not come on until the temperature is 1, 2, or 3 degrees higher than the current setting, and not turn off until its that far below. Good for furnances and A/C units where you don't want them constantly turning on and off.

When you open the box you will get a bunch of stickers that correspond to the letters printed on the terminals of your new and old thermostats. You attach the stickers around each wire before unscrewing a single one. Then you detatch the old thermostat.

Then you simply attach the labeled wires to the labeled terminals on the new one.

[alyxyn.livejournal.com]

$400 for just gas, for only last month? Dude, you don't need a new thermostat, you need to check your windows and doors for drafts and the insulation in your walls. Are those single pane windows? Do you have storm windows? I'm heating 3 floors with gas, don't have a programmable thermostat, and it was a bit over $100, and that included the electricity I used.

Follow-up on slinkr's suggestion to get in touch with the gas company. They can not only help with the thermostat, they will come out and do an energy efficiency check on your whole house and give you recommendations on how to improve things.

[gravitrue.livejournal.com]

totally. they have these awesome IR cameras they use to check leaks.

Also, long-term, look at the heat system and see if it can be improved. can you keep the bedrooms warm at night without heating the whole place? are some rooms too hot and others too cool?

If you have recirculating hot water, make sure the system is bled properly. If one-pipe steam, get variable air vents for the radiators. Make sure all radiators can convect properly; cool air in at bottom, warm air out the top. Consider adding zones if that would make sense for your usage patterns.

Remember, this isn't just money, this is global warming. I.E., whether or not the entire human race dies.

[keyne.livejournal.com]

I pay a lot more than that most winter months, with natural-gas heat -- but I'm in a four-level house in New England, with a lot of square footage. (And yes, the gas and electric companies came out years ago to do their thing. They didn't do much for us but leave a bunch of CF bulbs behind :))

[yesthattom.livejournal.com]

This is a 3-story.

[yesthattom.livejournal.com]

Yes, we're already started a survey of where the heat is leaking. Most of the windows are brand new and very modern with respect to energy conservation, but there are a few that are old and leaky.

[alyxyn.livejournal.com]

As a comparison to your home, mine is an end-unit townhouse, 2 floors plus a partially finished basement and an unfinished garage, a bit over 3200 square feet of living area, a boatload of windows, particularly on the main floor, and nearly new. And, as I said, I had a bit over $100 in gas & electric last month compared to your $400 with almost identical weather conditions.

Given what you've reported so far, I'm betting that your moneypit is caused by inadequate or poorly installed insulation. What's the R-rating of the wall and attic insulation, and how old is it? Are you forced air heat, and was this installed after the house was built? If so, then I'd definitely suspect things like poor insulation, particularly around any vents to the outside and possibly leaking and/or poorly insulated ductwork. There may also be draft problems around the duct openings into the various rooms. (Dang. Watching This Old House for years may finally be paying off! You do have a CO detector, at least near the furnace and water heater, right?) You might also want to check on how old the furnace and water heater are; if they're over 10 years old, it might be worth it to replace them with new, high-efficiency units.

Good luck tracking it all down, at least, and I hope you get a cork in the hole, soon.

[whc.livejournal.com]

If it's heating only there are probably only two wires (three if there's a setting to run the fan only), so it should be pretty easy.

The worst case can be pretty confusing. I tried to replace one on a combination oil furnace and A/C. There's an extra wire that is labeled, but is not mentioned in the instructions, and is unknown to tech support at both the makers of the original and new thermostat. I assume I can figure out what it does by tracing the wiring inside the old thermostat, but haven't taken the time yet.

It's a snap

[mrfantasy.livejournal.com]

If you've built a PC you can swap a thermostat.

$400 is a lot, but the house is pretty big so that may be some of it. You may want to check the insulation in the attic areas and add if possible. I forget what's up there, but I don't think it was much. Hopefully they insulated the walls when they redid the clapboards. Also, I forget how old your furnace/boiler is but if it's older than about 20 years it might be worth replacing. I'd be happy to help out with what I know of such things.

[dawn-guy.livejournal.com]

Your dollar's bigger than my dollar, I have a largish 80 year old house in a similar climate, and my gas bills have never topped $300 even in the biting days of February. I have no idea if your federal, state or local government offers energy efficiency incentives, but here is a good starting point to saving money on future heating and cooling bills.

[entirelysonja.livejournal.com]

I have two programmable thermostats; installing them was a piece of cake.

Mine happen to be from Honeywell; I picked them up at my local Home Depot. The main things I was looking for were the ability to program the weekdays and weekends separately, and the ability to put the program "on hold" for some specified number of days so you could keep the house at some economical temperature when you were on vacation, but still come back to a reasonably warm (or cool, in the case of air conditioning) house.

The specific model I have doesn't seem to be available anymore.

[qwrrty.livejournal.com]

I replaced our flaky programmable thermostat with a newer, un-flaky programmable thermostat. Was a snap, and I have very little DIY homeowner experience to draw upon. Like everyone else said, make a careful note of how the wires are connected to the existing thermostat, and use that as your guide to which ones are ground, heating, etc. Our new thermostat included descriptions of how to deal with at least three common wiring configurations.

FYI, your link didn't work for me -- it complained that my (your?) session had timed out.

[awfief.livejournal.com]

Not much more to add than what folks already have said.

Except this -- buy one (I believe you can get decent ones for $40 at Home Depot, so cost is low -- a friend did this a year or so ago to save $$, and she's not a computer person. In her case, the color & number of wires matched what was expected in the instructions).

Try it out.

Have a rollback plan.

I can't imagine you'd end up much worse than your current situation -- $40 in the hole and a bit of time, perhaps, but that's the worst case scenario. And you're probably part of the best case scenario -- follow the directions and have it Just Work (TM).

[stitchinthyme.livejournal.com]

Everyone else has already answered, but I thought I'd add that Ray's replaced several of our thermostats over the years and he says it's simple. And he's not exactly Mr. Fix-It.