3 Bar Pumped Cold And Hot Not Working

[JackK]

I have invested a ton of money of a new Stuart Turner monsoon pump which has been plumbed to feed all the water outlets in the house (expect for cold water mains).

I have a 22mm pipe which feeds the thermostatic shower and there is a tee for how and cold water to tap basin - I have Hansgrohe taps installed.

When I switch on the cold water the pressure is adequate and acceptable however when I switch on the hot water the pressure is pure - In both cases I can hear the Stuart Turner pump come on so its really puzzling.

I have checked isolation valves and they are all fine


Can anyone give me any ideas before I have to pull out the vanity unit and do a bucket test on the pipes without the taps in place?

I have a video but cannot upload it sadly! Hanshgrohe technical have been useless so far!

 

[oldbuffer]

1. Which model of Monsoon?
2. How has it been installed? Fully in accordance with manufacturer's instructions?
3. Pictures of pump and connections to hot water cylinder and cold water storage cistern please.

 

[JackK]

Hi I am in the office so cant take pictures till later tonight

It is the monsoon universal pump - Was 575 from Screwfix

I have cold water from storage tank in 22mm pipeowrk
I have hot water from side flange of cylinder to pump
Pipes in and out of pump are on 22mm copper pipes

There is 22mm pipe work which is used for ensuite shower and then teed off for a vanity unit. For the vanity unit it reduces to 15mm at the metre of length

What is weird is that both hot and cold water to vanity is 15mm for last metre and the cold is acceptable but the hot is slow - The shower which reuses the pipework is powerful and acceptable

Really peculiar

 

[JackK]