Is it difficult to replace a thermostat? I have hot water baseboard
heat and was thinking of replacing the thermostat in one room with a
programable. I have three zones but this one zone is the one I need
to change the settings on the most.
In most cases it is rather simple One of the best brand is Honeywell.
There are instructions in the package. Chances are, you have two wires to
the present Tstat. If so, just attach them as the instructions say, mount
the base and then mount the unit.
9 of 10 times it will be a no brainer - easier than replacing a light
fixture - same degree of difficulty (2 of 10) but much safer because it's
What I would recommend is this: take off the old t-stat and remember which
wires go to which terminals. Likely you'll see them connected to the
terminal which is marked for that color (e.g red, green, brown, yellow, etc.
wires; terminals marked r, g, b, y, etc.). If so, you'll likely have no
problem with new tstat. If not, just be sure to remember which goes where.
Like if you have a black wire that's connected to the terminal marked "g",
remember that because you'll want to connect it to the "g" terminal of the
Then, look at the instructions for the t-stat you're thinking of buying.
Open the package and look at the instructions. You're just looking to see
if it makes sense for the way your old one was wired. 9 of 10 times it will
be that the old tstat has colored wires connected to the same designated
termila and if the new tstat requires the same number of wires as the old
one (e.g. two or three). Or, many/most? have instructions or two or three
wire installation and various combinations of heat and cool. Just make sure
that it makes sense ahead of time, I'm almost positive it will.
I once ran into a difficulty because my old tstat (IIRC) was two wire and
the new one was three and I had to figure out which should carry voltage at
what time, etc. There were three wires running up to the t-stat but only
two were connected down at the furnace / zone valve/ transformer area so I
had to figure out how to connect it down there. It took a while with a
multimeter to figure it out but was not brain surgery. My wife thought I
was gold-bricking because I've actually changed t-stats a bunch of times (to
replace worn ones and then to switch over to programmable). and it always
took just a few minutes.
FYI - your situation is similar to what I had. I bought a Honeywell
7500, which works for my gas boiler/hot water fin-tube system. With a
little help from some friendly people in this forum, I was able to
change it out in a few minutes.
A couple of notes:
- the temperature of the digital thermostat varies by as much as
5degrees from my old mercury one (and several other non-digitals that I
had in the house)
- it took the unit about a week to really get a handle on adaptation.
It didn't help that the temps fluctuated quite a bit, so just note that
the first few days may differ from what you see thereafter.
- the difference in my first month's usage from previous months was
about 6% using a 5 degree adjustment at night (wife is home during the
I am very happy with the purchase so far and would recommend contacting
vendors to make sure you get the right type of stat for your home. I
chose the 7500 on various advice I had received, reputation of
Honeywell units, and the fact that I may replace my heating unit in the
future and it can handle different types of systems. Disclaimer: I am
not affiliated with Honeywell.
HomeOwnersHub.com is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here.
All logos and trade names are the property of their respective owners.