Zone 3 return is cool to the touch...

yaca

Hi ALL, I had the circulator pumps moved to the supply side of each zone and also added 3 check valves on return side for each zone along with The water feed to to expansion tank. The grunfos circulators have internal check valves. So if the first floor stat calls for heat , supply side of that zone is hot to touch however whereas the return is cool. I purged the system of air but need some help on trying to resolve. Any suggestions greatly appreciated

JOutterbridge

Are you sure you properly purged the system? If it's all water and let's say 15psi of water, your returns should heat up as the water flows. And are you saying you have 3 zone valves and 3 floating checks and 3 pumps with internal flo checks too? If so its redundant. You need to verify that all air is out of the loops 1 by 1

HVACNUT

Can you post some pics?
If piped right there shouldn't be a problem.

yaca

I’ll try to purge it zone by zone , thanks...and each zone starts with a grunfos circulator equipped with an internal check valve then hard pipe to heat emitters (mostly baseboard and a cast iron radiator at the end of each zone before it returns home ) however I did install a manually operated check valve on the return directly before manifold. So, each zone starts from the manifold with a circulator with internal check valve, , heat emitter, manual check valve on the return before the return manifold. There are no electrical zone valves or flow switches all manual or spring activated. I used the layout as described in the book pumping away. On the supply directly before expansion tank a webstone ball drain so if I followed correctly should purge nicely. The only other addition was a Caleffi water feed to expansion tank with the webstone fitting,which worked great. It filled the system quickly and its set at 15 psi.


Will try to add pics .
Thanks

yaca

Thanks for the support ! System working great now. A thought on purging, what would be the ideal pressure setting to purge a 3/4 copper pipe zone considering the flow rate. I’ve read six to seven gpm but wonder what pressure setting it would be. Still have some small pinging on first floor zone so I set the water feed to 20 psi to maybe digest the remaining air, any thoughts on pressure settings?

hot_rod

Pinging or ticking could be the tube expanding, not necessarily an air issue.

If you have a Caleffi 573 fill valve it will flow 5.2 gpm regardless of what pressure you set, no need to boost pressure to fill. That should be plenty flow to flush and purge a 3/4 zone.

12- 15 psi should be adequate system pressure, read it when the system is cold, it will increase as the water warms.