Sting wrote:There is no one single reason or silver bullet to fix when return temps are too hi - or exceed the optumum
but consider why the return water is still to hot????
I didn't make myself clear. When my supply is at 180 degrees, my return is less than 160 degrees. More like 150 degrees.
I guess much of this depends upon when the supply/return temperatures are taken. Eventually the zones heat up and the T-Stats are satisfied and they shut off. When should I measure the supply/return temps? Shortly after a zone valve opens and the return loop feels hot, or closer to when the zone is satisfied and about ready to shut off?