Indirect Coil Problem

[Andy4444]

As usual been round the houses looking for a solution before posting this topic.
Have a customer complaining that she has no hot water. She has an open-vented fully pumped system with an indirect hot water cylinder. With hot water ON the flow pipe into the cylinder coil heats up however the return pipe from the cylinder remains cold.

Could this be an airlock/blockage in coil etc?

btw - The pump is on its way out (I managed to get it working for a short while but it then died on me....customer advises that she has had problems with the pump for some time now).

Suggestions/solutions gents would be much appreciated.....

 

[bellairaphon]

more than likely a airlock is there no manual vents or have u not cracked the cylinder connections

 

[namsag]

If its fully pumped system then you have answered own question ..pump.

 

[JohnD]

you have checked that there is enough water in the system and no blockage? I had this in my old mum's system and was expecting a blocked F&E pipe junction, when I got my stuff together and clambered into the loft I discovered the F&E tank was empty due to a seized ballcock.

I am a householderr not a pro

on re-reading I agree - fix the pump

and as it is open vented I bet it has a good load of sediment