Newbie Needs Assistance

[CombatVetFamilyMan]

Ok folks, plumber connected the forward and return manifolds together and added a check valve (cite pictures). it has been warm the past few days. finally cold out today so I fired it up hoping the problem would be solved. It was not. The 2nd floor circ was not running as that zone was not calling for heat however hot water was still flowing right on through the pump to the 2nd floor. Maybe replace the pump?

 

[maple1]

Is flow going past your overheat zone valve? That's one thing to rule out while there's a fire going - the dump circuit not being right.

I'm thinking you might need either a check valve with more resistance to it than the one built into the pump, or a zone valve installed there for that zone. I'm doubtful a new pump will help - unless the internal check is somehow messed up. Whatever the problem is though, it's not you - I'd keep after them until they get it fixed, since it's a new install.

One more thing I'd check though - are you sure the circ is not running for that zone all the time? Maybe un-wire it temporarily to see if that makes a difference. Sometimes it is very hard to tell if they're running or not, they run pretty quiet. If un-wiring the pump stops it, there must be a control issue - e.g. if it's plumbed to dump heat in the second floor, it somehow thinks it's too hot all the time. Or maybe an overheat aquastat just needs turned up (outside chance of that likely). But we still don't know much about your dumping/overheat setup, as it's not on their diagram.