Heating, Air Conditioning, Fridge, HVAC/heating problem


QUESTION: I have just added an addition on to my home and had force hot water heating installed with a thermostat. It seems that even when the thermostat is completely shut off the heat still comes on when the other downstairs thermostat comes on. We also have a thermostat installed in our upstairs space that is turned off and this space does not get heat unless the thermostat is turned on. Because this is a new addition which was quite expensive it is irritating me to no end.

Thank you for your consideration in this matter.

Len Sherlinski

ANSWER: Hi Len, It's sounds like they piped the the new zone into the existing zone instead of adding a separate zone. Did they add a new zone valve? Can you send me any pictures?

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heating pipes
heating pipes  
QUESTION: Jim, as requested here is a photo of the set up going into the furnace. The valve in the forefront is the new addition.

ANSWER: Hey Len, Thanks for the pic. This valve is a normally closed valve. Meaning it has to have 24V to open. Label the three wires on the valve, then remove the wires one at a time and tape them off. Turn the old stat on the first floor up to call for heat. You should get heat to the old zone only. If you get heat to both zones then the valve is stuck in the open position.

Let me know what happens.

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QUESTION: Jim, I am not sure what you mean by a 24V to open, can you explain?
Otherwise I do believe I understand what you are saying, my one last question is, after I pull and label the three wires and turn the old stat on do I reconnect them at anytime or just leave them taped permanently?

Len,First check the lever on the valve. It is located to the left of the wire terminals. Make sure it is in the up position.

The valve needs 24v from the control board to open. So I'm thinking the board is sending 24V all the time or the valve is stuck open. I would reconnect the wires to the valve after testing.

Heating, Air Conditioning, Fridge, HVAC

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Jim S.


I can answer questions on gas or electric furnaces, ac units and heat pumps. I don't work on boilers,chillers,or home appliances.


I have been in the HVAC trade for over 35 years. For the past 15 years I have owned my own business. I am semi-retired so I can answer questions in a timely manner.

I attended trade school for 5 years on weekends and evenings. This was very hard to do, but well worth it!

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