UFH Return pipe is hot and flow is cold

[Rizwan Ahmed]

Hi

Sorry if l don't given enough information new to this.

Just had new UFH installed but doesn't seem to be working, gas engineer who connected the flow and return cant see an issue with the piping itself.

He changed the pipe and put a zone valve on the UFH

But when he turns it on noting happens but when he turns the hot water on the does turn on the UFH but the return pipe is getting really hot and the flow is'nt. He has double checked all the piping and cant seem to figure it out.


Anyone else encounter a similar issue or has anyone got advice on what needs to be checked

 

[oilhead]

It wouldn't be the first pump I've seen installed backwards. Have a look at the arrow on the body to check direction.

 

[Rizwan Ahmed]

Hi

I have just checked that and the arrow is pointing up I have attached 2 pics I am assuming it should be going up.

 

[cross thread]

Have you the Install instructions ? I think the flow should be the one inline with the pump

 

[oilhead]

Which return gets hot? The return from the UFH into the mixing valve, or the return from the mixing valve to the boiler? If the latter, then the flow and returns from the boiler must be reversed.

 

[Madrab]

The answer's on the mixing valve tappings - The 'R' denotes the return, i.e. the Right 'R' is the retun from the manifold and the left 'R' is the return out to the boiler therefore if the left hand red valve with the 2 port on it is actually the flow from the boiler, then the plumber hasn't piped it correctly.

The tapping at the bottom of the mixing valve will have an F on it, denoting the flow side of the valve. You need it re-piped correctly and your plumber needs to read the manual.