I've encountered this a handful of times and it's good one to throw a tech for a loop. You have a system falling behind. You arrive and find it hitting limit within a minute or 2. Filter is clean and blower speeds is in high. Gas pressure is correct. You have also confirmed temp split is high and limit is correct and functional. You take static pressure and find these numbers. What's going on? Pre filter-.25 Return-.35 Supply-.20 Post A coil- .09 There are some oddball things I've seen cause similar numbers.

Posted by Dick. C at 2021-03-29 18:29:14 UTC