It's hard to say. You really need a good tech to come out and take a
look, do the computations and make some suggestions.
As noted, adding insulation, if there is little or none can help and
having the blower on full time can help, but heat rises so I'll bet it is
not going to be easy as it appears the current system is not well designed.
On the other hand, the current system may be fine, but someone has
screwed up the balance.
I don't recommend blocking off many vents as it can cause problems with
Joseph E. Meehan
26 + 6 = 1 It's Irish Math
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