Any HVAC guys here? We have a problem....

[Karen]

Bought our house last year.....ranch with full, unfinished basement. Maybe 1600 sq. feet. Hot water baseboard oil heat with 3 zones.

The master bedroom & bath is 1 zone
The rest of the main floor is another zone (2 bedrooms, 1 bath, living room, dining room, kitchen, office)
We had a 3rd zone put in when we moved in to heat the dog room in the basement (a 12 x 20 room)

Right now the heat is off in the master bedroom, yet the baseboards are warm and it's 75 degrees in there. The rest of the house is 68 degrees.

What would cause the baseboards in a room with the zone turned completely off to be warm?

[ibbowhunting]

Are the zones controlled by pumps or zone valves?, meaning you may have 3-4 pumps or one or two depending on the way it's plumbed

[cjhills]

Zone valve stuck open or leaking . Water bypassing valve or back feeding. Was this a problem last winter? If not zone valve problem. Maybe thermostat but not if valve is closed and turned off.
Is the system all on one pump?

[Karen]

Zones r controlled with pumps. Had the issue briefly in the spring but when we turned emergency switch off and back on it resolved. That didnt work this time.

[crazyboy]

Is the circulator pump for that zone stuck on? In my experience circulator pumps are much more reliable than zone valves so I'm surprised you're having an issue. If you leave the emergency switch off does it cool down? If the circulator pump is constantly running, will it shut off if you disconnect the thermostat? If so, replace the thermostat. If not, sounds like it might be a bad controller.

[Karen]

Yes, it cools down when emergency switch is off. Had it looked at last time it did this and was told the pump was off And tgey couldnt find anything wrong. Could it still leak? And the thermostat has slready been replaced twice.

[ibbowhunting]

sometimes the pumps will allow flow thru them, which I would call ghosting, sometimes due to other zones running or just gravity, guessing the boiler is lower then the zone in question(heat raises) the easiest way I know of is to replace the pump with a grunfos ups 15- 58 pump with check valve, or similar but with an internal check this should be an easy fix four bolts and reconnect three wire if the pump has isolation flanges if not you have to drain the boiler

[Karen]

Thanks guys! Sounds like we need to replace the pump. John hiked the heat WAY up in the bedroom so it would actually kick on, then turned it down to a normal temp, and that seems to have closed the valve p(or whatever it is), and the temp is now droping in there, thank goodness!