Posted By docjenser on 07 Aug 2012 03:02 AM
Minimal EWT of 30F usually means an AVERAGE SEASONAL COP of 38F.

Is this true, I have no measuring stick (yet) and do we know what the winter was like for the referenced study (mild, severe etc.) to make the assumption that the system wasn't over engineered?

Posted By docjenser on 10 Aug 2012 02:40 AM
Need your piping layout, length, diameter etc. Also heatpump type and model

Since this is a subject substantially different from 'Independent U.S. Study Measuring COP' I'm going to start a new thread.

Best regards,

Bill

Posted By joe.ami on 10 Aug 2012 09:58 AM

Posted By docjenser on 07 Aug 2012 03:02 AM
Minimal EWT of 30F usually means an AVERAGESEASONAL COP of 38F.

Is this true, I have no measuring stick (yet) and do we know what the winter was like for the referenced study (mild, severe etc.) to make the assumption that the system wasn't over engineered?

That's what our monitoring reveals, with average temps, summer a/c, DSH etc. Run some design software (CM, Waterfurnace), you get the same results. Shoot for min loop temp of 30F, your average loop temp in heating mode will be around 38F.