I have a Coleman FC9C (80K BTU/1200CFM) and an old home with poorly sized ducts. It took a long time to get someone to come out but the NCI Specialist came by today for an initial consultation.
He said he would put together a proposal to 1) come out and take readings/measurements then 2) come up with a plan to correct the system.
First impressions were that supply may be OK but return is definitely a problem. He also made a comment about the fiilter. Said given all the air flow restrictions the cheap blue spun glass filters would be better as long as they are replaced monthly.
Initially I passed on the blue filters and went one step up to the white pleated Merv 7 or 8 filters.
Is it ok to use these filters? I have enough problems without adding more to the mix by using an improper filters?