THPRE

[beenthere]

Ok but if the system was wide open in the return and had a 16in. duct removed from the plenum and I was still watching 610psi to 400psi in under 1 minute cycles there must be a further prob;lem? I mean that with sstatic pressure minimal and cfm close to 2100 there should not be an air flow problem causing the 610 high side?

Might mean they had to over charge it in cooling mode to make it work with the low air flow.