Freeing seized Grundfos Amazon shower pump

[ChrisOxford]

Hello,

My parents had a Wickes twin impeller, 3 Bar shower pump installed about 2 years ago. It's only used now and again when they have guests, and surprise surprise, has seized. When there's a call for water, it buzzes and gets warm but doesn't actually run. The showers "work", but the flow rate is pathetic.

It seems to be a rebadged Grundfos Amazon twin impeller STP-something and the helpline listed in the instructions takes you to the Grundfos help desk. They advised tapping the brass impeller housings at etiher side with a mallet while calling for water but this didn't do the trick.

What next, please? I'm a reasonably competent DIY plumber but don't want to drain everything down if possible. The gate valves are old and I'm not sure they work as well as they should.

Cheers.

 

[just pumps]

As far as I`m aware you will need to isolate the incomings and remove the cold side end cover. Oxford has very hard water.

 

[ChrisOxford]

Thanks for the reply.

It's this one, Wickes code 160404 @ £269.99: https://www.wickes.co.uk/Wickes-Twin-Impeller-Shower-Pump-3-Bar/p/160404

It turned out to be an easy fix. I isolated the cold feed after freeing-up the stuck gate valve, undid the four very tight Pozidriv bolts holding the cold side brass housing to the motor body, then popped off the cover to expose the impeller. A few twists by hand was all that it needed to get it spinning easily. Reassembly was quick too but the bits have to be aligned correctly (I should have marked it before dismantling!) and of course the O-ring needs to be sat properly. I then switched the water back on and ran a shower for a couple of minutes before switching the electrical supply back on. Result! No leaks and a decent shower again.

The Grundfos tech helpline (whose number is given in the Wickes installation booklet) said that if bashing it with a mallet didn't work, it needed to be returned to Wickes for refund or replacement, which surprised me as in-situ repair was hardly rocket science.

C.

 

[just pumps]

Glad my suggestion worked, now and then run the shower and it shouldn`t stick again. Also check for any weeps of water after a couple of days.

 

[ChrisOxford]

Cheers, will do as you suggest.

C.