Hydronic Zone Valve Partially Open

[alkalinebubble]

BLUF: is it okay to leave a hydronic zone valve partially open?

I have a hydronic baseboard system, c1982, that’s in good working order but the head unit on the upstairs zone valve failed open. I took it off and while I was sourcing a new one, I left the valve about 1/2 open to trickle heat thru that zone. The head units are normally all on or off.

Normally the heat cycles are too big for my comfort so I’m constantly taking the blankets on and off. The downstairs zone thermostat is modulating heat for the whole house but the upstairs is more constant.

Is it okay to leave the upstairs zone fixed halfway open? I don't know the design of the valve. I don't hear any cavitation through the valve. The boiler isn't firing any more than usual.

Reference: https://a.co/d/00qrSNev

 

[MaxBlack]

I have a different boiler system but have had two zone valves fail recently so your post caught my eye. I don't see a partially open valve being any kind of problem besides possibly "gets too hot" in that area and/or it siphons hot water from other zones that need it more.

It's now weeks later and maybe you never come back here (a "one-post wonder") but this is a subject I know something about!

And BTW ain't it a trip to figure-out how to set things to have comfort all day and all night. It's taken me a while but I've finally learned how to deal with the fact that such systems a.) retain heat long after turn-off, and b.) take much longer to bring a space up to temperature (depending of course on your setback/ambient and OAT).

 

[Sponsor]

 

[alkalinebubble]

Thanks for the reply!

I’ve left it partially open and it’s been working fine. I realized though that it—of course— won’t circulate without the circulator on. So it circulates when the downstairs heat flips on. But in my case this is fine at night with less temperature swings. The only drawback is I’m wasting heat upstairs during the day.

I’m thinking of a project to build a valve modulator with a stepper motor on an Arduino and have an AI learn to modulate the valve and control the circulator. Kind of like this tomato plant project, but for people

Claude is growing a tomato plant

Dries is the Founder and Project Lead of Drupal and the Co-founder and Executive Chair of Acquia.

dri.es

 

[Fitter30]

Zone valves the operators can be removed without removing the valve. The shaft can be checked. Shouldn't be hard to turn. Complete model of valve tell ifvvalve is n.o. or n.c. voltage and end switch/s.

 

[John Gayewski]

Zone valves aren't meant to be half open or half closed. There are different types of zone valves. I would recommend fixing the zone valve so it operates as designed. If you want to control individual heat emiters you need a thermostatic valve near the emiter. There are other techniques to balance heat in a system, but a thermostatic valves are meant to open and close according to the air temp in the space they are installed.