Twin Impeller shower pump broken?

[harrimf]

I recently lost all pressure to my downstairs shower.

I have been having problems for a couple of weeks where the shower temperature slowly gets colder. I think the thermostatic control may be damaged as the dial turns constantly in either direction, although the temperature can still be controlled to a degree.

The other day the pressure went and while doing some testing I noted smoke coming from the pump.

I'm not sure whether the pump is broken, or just has a dry cavity, or there is a problem with the feeds. Additionally I do not want to replace the pump if a problematic thermostatic shower valve could cause damage to the new pump.

Any advise on how I can diagnose the issue would be appreciated!

 

[duffin]

turn off pump at mains, disconnect outlets and run them into a bucket. turn on mains- for a very short time. should be able to tell if pump or shower is gone. my money on pump. twin impeller? around a ton.

 

[Agile]

£100 for a shower pump?

Well yes, for a cheapo plastic one.

But a quality pump like a Stuart Turner will be about £400+ and thats just to buy it !

Most pumps will run happily into a no flow outlet.

Sounds like the OP has a failed pump and a failed shower unit!

Tony

 

[harrimf]

Thanks for the input.

I suspect I have broken shower and pump. I'll test the pump tonight and as suggested above and see whats what.

 

[harrimf]

OK so pump replaced and shower was OK for about 2 days, by OK i mean better than before but still not very hot. Anyway, the hot water seems to have petered out entirely.

I have tested the feed from the hot water tank to the pump (into a bucket) and there is plenty of pressure.
I have disconnected the thermostatic valve at the shower end and run the water straight through, bypassing the pump and I just get a dribble at the shower end. I cant even blow through the pipe. I've stripped it back to the non-return valve but from there the pipe disappears under the floor.

Any ideas? I suspect a blockage as found a load of black gunk in the non-return valve. However, from reading other threads could it be an airlock?