Bad Flow-Check Valve?

Sandro

I just finished installing a TACO SR503 relay module. The purpose was to convert the line voltage thermostats to low voltage. Everything went fairly smoothly with the exception of the aquastat wiring but I’m fairly certain that is also correct. It's a three zone Hydronic system. The problem is that after I was done installing the relay module on of my zones started to get hot without the circulator turning on. The only thing I can think of is that the Flow-Check valve for that zone went bad. Before I replace it I'd like your opinion, did I miss something or is it just a coincident.

Thanks for your help.

Brad White_2

It might be that

the flow check is in the "manual" position (designed for at least gravity flow in case of pump failure).

Depending on the manufacturer of flow check valve, it may be required to be turned all the way clockwise or counter-clockwise for "normal" operation.

Look for words like "Manual" or "Open" or "Run" in the casting near the knob on top. See if you can find the instruction sheet that came with it, when all else fails.

If in doubt of which way to turn it, try each way.

Good luck.

jaybee

flow check valve

What is the purpose of a flow check valve and where is it used in hydronic system?

Sandro

I think I got it.

Thanks Brad but I think I got it. After reading someone else’s post about a bad flow-check, I did what he recommended and tapped it a couple of times. Sure enough about an hour later the pipe on one side of the valve was cold and the other side was hot. I have no doubt that I have an intermittent valve.

lchmb

used

in a system that is controlled by circulators for each zone a flow check stop's flow through a zone that is not calling for heat. It is not needed on a system controlled by zone valves. Hope this helps...