New shower pump problem

[pezza]

I have recently had a new shower pump fitted to replace an old one that worked ok for 14 years. The new pump was advertised as a direct replacement for the old one. After about 10 minutes of use the pump squeals or whistles intermittently until the shower is turned off. If I turn the power off to the pump when it is squealing and turn it back on after 5 seconds, the pump runs quietly for another 10 minutes.
A Surrey flange is fitted to the hw cistern, and the cold water supply to the pump is teed off the 22mm supply to the bath. The shower and bath are never used at the same time.
Any views on what is the likely cause of the noise problem would be much appreciated

 

[IDCHAPPY]

Sounds more like a pump issue than a pipework or feed issue TBH

 

[pezza]

Thanks. Is the manufacturer likely to quibble over the non dedicated cold water supply to the pump?

 

[PlumbBobBob]

yes probably. is the cold feed to the bath mains or tank fed?

 

[Centralheatking]

It seems to be a like for like replacement problem - which we really cannot do on here CHK :rockon2:

 

[pezza]

Thanks steveb. From the tank. The outlets in the tank to the bath and cistern are on the same side of the tank as the ball valve. Is this a problem?

 

[Ray Stafford]

Thanks. Is the manufacturer likely to quibble over the non dedicated cold water supply to the pump?

Probably, but more likely with some manufacturers, and some models than with others.

Generally speaking, regenerative pumps seem more forgiving of this than centrifugal pumps.