What type of check valve ?

[wobbin]

Hi all,

I have a mixer shower (Newteam) which is fed from the hot water cylinder (via a special flange of some sort I believe).

When it's first started up it sounds like it's pumping air for a while before the water starts to come out and the pump motor goes nuts. It doesn't appear to have any check valves in the 15mm supply pipes..... should there be, and if so do I need the single or double type ?

Thanks in advance.

Kind Regards,
Robin

 

[Softus]

It sounds as though it's been poorly piped.

Any photos?

 

[wobbin]

Sorry, no - not without major upheaval in the loft I'm afraid.

I recently replaced the shower as the motor brushes had worn out and I couldn't get any replacements, it was a like for like swap almost, same make, fixing centres and pipe inlet positions, the only difference being that the new shower didn't have a speed control.

The new shower unit is a New Team 1000XT Thermostatic.

The old shower didn't have the same issue so I wasn't suspecting an original installation issue (but maybe I've cocked something up or there were internal check valves on the old shower which aren't present on the new shower perhaps ?)

There are no leaks as far as I can I can see. I was wondering whether there was a small air leak which was allowing one of the feed pipes to drain, hence the question about check valves.

Would you normally fit check valves in the feed pipes ?

T.I.A

 

[Softus]

Sorry, no - not without major upheaval in the loft I'm afraid.

OK, but the more interesting pipework is where it connects to the DHW cylinder, or outlet from that.

Would you normally fit check valves in the feed pipes ?

Not without thinking about why I was doing it. For example, there are valves that mix mains cold and stored hot, and for many reasons I would fit a check valve on both supplied.

You might find that a check valve makes your symptom go away, but if aeration is the underlying problem then it won't fix the problem.