Shower pump query - uneven pressures H&C

[oceanbassboy]

Hi,

I have a Mira PPT3 feeding 2 showers. The pressure of the cold feed to both showers is significantly lower than the pressure to the hot. I have checked that both sides of the pump work independently.

The cold feed to the pump is gravity fed 22mm and the feed to the hot side is tee'd of the outlet 22mm pipe at the top of the cylinder.

The pump outlets have some kind of PRV's fitted and the cold side shows evidence of leakage at the valve.

1) Should I expect a significant difference from the H&C feeds?
2) Is it possible that one side of the pump is not as efficient as the other?
3) Is it possible the PRV is having an effect on the cold side.

Cheers in advance View media item 17167 View media item 17168 View media item 17169

 

[seco services]

check the filters on the flexi inlets.
check the check valves on the flexi outlets.

 

[oceanbassboy]

Thanks Seco.

The cold filter was full of sand! must clean the tank...

Having sorted that, now the pump keeps intermitttently running on the cold side and there is an ominous rumbling in time with the pump surges coming from under the carpet in the bedroom where the shower pipes lead onto bathroom 2... explains why there was much less pressure in that shower. time to get the carpets up eek!

 

[seco services]

i'd be checking the check valves in the outlet side if they don't shut fully when the pumps off they can cause the pump to keep surging and also air in the pipework probably where you isolated the cold to check the filters.

check the air vent it may not be letting air out.
and i'd fit a new one to the hot.

 

[oceanbassboy]

Thanks again Seco,

A quick play with the air vent (so thats what they are! a short pssscht and we are good to go.

I have checked with the Mira spares document and i don't seem to have any check valves fitted, the flexi connects directly to the pump out with just a rubber washer/o ring. Is this likely to present a problem in the future?

 

[seco services]

if its been ok in the past and its ok again now leave it.