Installing check valves in a two zone system.

JackW

I am redoing my radiant heating system in my Morton building, all piping is 3/4". It is a two zone system, each zone is controlled by a pump. In the old setup I kept the temperature in zone 2 higher and never had to set the thermostat in zone 1 because the zone 2 pump would pull water past the zone 1 pump heating zone 1, not as warm as zone 2 but ok. I want to put check valves ahead of the pumps to prevent this parasitic draw but I'm afraid the 3/4" check valves will restrict the flow. When in the open position the stopper hangs partially down which I would think would restrict the water flow. Is this a concern or not? Any thoughts on this will be greatly appreciated.

Thanks,
Jack

Zman

Unless your pump sizing is marginal, the addition of the check should not be an issue.

JackW

Good to know, thank you for your response.

Simply Rad

Grundfos 3 speed pumps come with integral check valves

JackW

Thanks Simply Rad I'll look into that.