Honeywell thermostat replacement

nother_new_homeowner

Hello all,

I replaced my old honeywell t87 mercury t-stat with a new ct87k heat only and now my heat seems to short cycle.

I set the dip switch to 2 on and left the first switch off as the chart indicated in the instructions for hot water heat.

Did I mess something up? Any help would be appreciated.

TIA

Jamie Hall

Why did you replace the old thermostat? The old one worked much better than the new one...

HVACNUT

Try putting both dip switches on.
A T5 might be a better option. Those T87 wannabes aren't the greatest. 

nother_new_homeowner

I replaced it because the room temp indicator was stuck on 72 degrees but the temp setting still worked ok.

I went and looked in the box after my first post earlier and the temp indicator was back down to room temp, so I took a straw and blew out the 75 years worth of dust as best i could and just re-installed it.

After looking around online it seems these are not indeed the best replacement for the old mercury activated ones.

I will monitor the situation, and thanks for the suggestions...

Jamie Hall

For a situation where you don't need programming, there is no good substitute for the old mercury ones, in my opinion.

EBEBRATT-Ed

I had those stats in my house and it started going wonky and I ripped it off the wall. They are flakey