Heating, Air Conditioning, Fridge, HVAC/Humidity in the house


We recently purchased a Tempstar 97 % variable speed gas modulated furnace. Our house humidty has gone to an average of about 65%. The new furnace takes combustion air from the outside. Our old furnace was 100k btu and our new furnace is 60k btu. Our old furnace was an 80% that got combust air from our garage. We are getting mold on things and the windows condense badly. What can we do to change the humidity back to 40% levels with that we had with our old furnace? Are we getting to much humidity with the new furnace?

In the heat mode when the furnace is heating it should pretty much dry up all the humidity in your house.
If your new furnace get's its combustion air from outside and exhausts to the outside there should be no connection with the house's inside air.
Furnaces don't produce humidity into the house if they are installed correctly.
The first thing that comes to mind with your situation is that your furnace may be putting carbon monoxide into the air.
Do you have a good working carbon monoxide detector in your house?
Also check other gas fired appliances.

Heating, Air Conditioning, Fridge, HVAC

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Jim Barnhart


Fifty + years conditioning the air.


Answer questions about , residential and commercial. Answer questions about sheet metal fabrication. Fifty years plus experience. No answers for oil equipment, No answers for kitchen appliances, No answers for laundry appliances, I don't specialize in one particular area of the HVAC area, I'm more of a General Practitioner, Limited in refrigeration/

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