wrote in message
oups.com...
Thanks to everyones input. The system checks out fine. Tech says it is
an air flow problem. He also plugged hole behind thermostat. He
suggests two things get a new thermostat with a different differential
(one you can set). The one I have has a half degree differential and
cannot be changed. Second is replace flex tubing ducts that run into
dining room with non flex duct.

I am wondering how replacing the flex duct would help. Most of the flex
duct I have ever seen or installed has a plastic spiral wound duct inside an
insulated cover for heating and cooling. The only flex duct that I have
ever used for exhaust fans is the metal uninsulated type. This is usually 4
inches and way to small to run for heating and cooling. Depending on the
situation this could get quite expensive to replace and insulate.

Seems an odd fix, to me. Especially the t-stat.



So I suspect with the new windows the air flow has changed and is
causing the problem.