grohe thermostatic mixer shower problem

[robbie77]

Hello,

I am puzzling on with my parent’s shower that works intermittently
It’s a grohe thermostatic mixer shower that is fed by an independent hot and
Cold water tank in the loft. The shower is pumped by a grohe active 75 pump.

I isolated the pump and removed the mixer bar and let the water come out under its own
pressure. I got good pressure from the cold but only a trickle from the hot.


I removed the fittings to the pump and pushed some wire down the pipes- nothing seemed blocked.
There is a little filter on the outlet that had some particles in but nothing major (about the same as the cold side).

What shall I try next? Shall I remove the pump and see if I can clean it?

Any advice welcomed!

Thanks

 

[seco services]

Are you getting good flow to/from the pump ?

 

[robbie77]

Hello,

Unfortuantely testing the flow before and after the pump is a bit of a problem as its in a loft of an old four bed stone house. I would need to find a fitting to attach to the the pump inlet and outlet and then get a hose on it and then find somewhere to feed the hose outside.
The pump has plastic screw on fittings that are hand tight.

Any advice on this or other tests I can do. The pump has grohe on it but also turner on the side!?

Thanks

 

[Dan Robinson]

Why are you spamming the forum with rantings on how you failed to fix a simple problem?

 

[HootingOwl]

So folks, if your shower is boolaxed just turn the knob to 4.5 and it will be repaired.
Treat the symptom without addressing the cause.