Wilo circurculator pump flanges with check valves

Doodybutch

I recently purchased Wilo Star-S 3 speed hydronic circulation pumps for replacement in an existing system. I also purchased matching Wilo flanges with integral check valves. The check valves are white plastic ball valves surrounded by black rubber bushings which fit into the flange.

The only thing holding the entire check valve assembly into the cast metal flange is the rubber bushing. I noticed immediately that I could just push on the check valve with my thumb using moderate pressure and I could easily push it in either direction right out of the flange. I could just as easily re-insert it into the flange.

Knowing Murphy's law from hard experience, I can't see why these check valves would not eventually float away into the boiler or piping and they would not necessarily stay in position in the flange. The flanges came with no instructions and no extra parts.

Am I missing something?

Thanks,

DB

SWEI

First, are you sure you actually need a flow check on this circulator?

The insert is intended to slide out of the pump end to facilitate service or replacement. Assuming the flanges have female threaded ends, try threading a short nipple in once you've installed the check valve. Does that prevent it from sliding out the pipe end?

Doodybutch

I actually did just that (3/4 inch x 6 inch nipple) and then I pushed the check valve and it fell right through the nipple into the manifold. The system has five pumps on one boiler so you need check valves somewhere. I think I'll just go with external sharkbite 3/4 inch check valves although they are more expensive. I don't trust the Wilo ones at all unless there's something I don't understand.

SWEI

Five PSC circulators fair bit of pumping power. Have you considered using a Wilo Stratos and zone valves instead?

Doodybutch

I thought of changing over to valves but it was easier to just replace the old Taco pumps without having to redo all the pipes.