Thermostat issue ?

[bigdog]

I have a digital Honeywell wall thermostat, and having issues.
This particular one is located on the first floor, as I have a 2 zone system.

I have the thermostat set at 65 degrees, but the temperate display is showing 77 degrees. The appl I have on my mobile also indicates 77
I've tried resetting, and shutting thermostat on/off but no change.
I recently replaced the battery with a fresh one.

Upstairs zone is set at 55 degrees, and noticiebly much cooler upstairs so assuming that is working OK. That thermostat is old Honeywell dial-type.

Thoughts on what is happening here before I run to Lowes for a new thermostat. Could the issue be at the furnace side for that zone, and ignoring the thermostat setting ?

Thanks for your feedback !

[8gv]

Call Honeywell.

They have likely seen this before.

Does it feel like 77 is correct?

[Reilly]

I would say flow check on boiler on that zone is stuck open allowing heat to gravity feed

[dpg]

Do you have forced hot water? If so the zone valve controlling that particular zone may be stuck open constantly sending hot water through the area...

[BroadHopper]

Problems with zone valve are common. Check the zone valve. Also check to see it the thermostat is clean of dust and that the thermostat is set to the right voltage in the line. There is a dial under the cover.

[bigdog]

Dpg & Broadhoper,
I believe you nailed it 'Zone Valve' !

Called oil dealer service and described the problem, and they said 'Zone Valve' !
It appears to be only 1 zone in question.
I have Taco Zone valve, and supposedly they can be replaced easily, screw off, screw on ! Service tech on his way.

Thanks to you both ! Will report back after Tech reviews.

[Biggd]

I had this problem many years ago. I had 3 zones and the main one would not shut down. I didn't have zone valves, I had separate circulators and check valves. I finally confirmed it was the check valve that was stuck open. I took apart the one that was sticking and found a piece of black rubber stuck holding the check valve open. Problem fixed, or so I thought.
A week later it did it again. I took the valve apart and found another piece of black rubber. Not knowing a whole lot about plumbing and heating I tolded my burner guy about what I found and he told me the expansion tank was coming apart inside. I changed the expansion tank and problem was solve for good.

[dpg]

bigdog - you lucked out pretty quick response this time of the year. Most of those folks right now are running like crazy.

[bigdog]

Have to give a shout out to my oil dealer 'Dutile Oil'.

Have been with them for 10 yrs now and they are rock solid on service !

Mike the owner is a great guy, and en expert trouble-shooter, and had this
one figured out in about 10 min ! :) Guess it's a common issue.

[dpg]

Have to give a shout out to my oil dealer 'Dutile Oil'.

Have been with them for 10 yrs now and they are rock solid on service !

Mike the owner is a great guy, and en expert trouble-shooter, and had this
one figured out in about 10 min ! :) Guess it's a common issue.

Actually happens all the time first line of defense for those folks to look into. Been there, done that! :rolleye2::eek: