Got that. I was just not thinking for a min. I had out conference with Goodman rep. by telephone friday. She wanted static pressures and has not replied since being given the numbers. static pressure numbers are ; return air w/outside vent on = .04 max. measured , supply side air .25 to .27 giving a total of .31 to .30. My understanding is that this puts air flow out as a source of my problem. During our test the unit took about ten min. to build up to 610psi then started cycling from 400 to 610 with the cycles becoming progressively shorter finally working down to less than 60 seconds for complete cycle. The other thing to keep in mind is that this unit has never worked even once in transition from hot to cool or back again!