Mixer Shower Screeching - Grohe

[OzWiz]

We have a Grohe mixer shower which makes an obnoxious screeching noise while running.

We used to be able to manage it by finding a quiet spot but have had a new boiler fitted recently and the problem is now very bad. The best case is a constant low drone and worse case is a high piched screech.

Please help!

 

[sparkytim]

Is it being starved of water?

 

[OzWiz]

Plenty of pressure, only time it's quiet is at a trickle... have tried taking the shower head off and running it but no real difference...

 

[NozSpark]

Is the hose OK?

I've had the inside wall collapse on me before!!

 

[Sidewinder]

where is the noise coming from?

have you tried it without the hose or with a diff hose as noz is hinting at?

 

[Manator]

The High pressure is 1.0 to 5.0 bar. The Low pressure is 0.1 to 1.0 bar

You need to say which head you are using, our resident Plumbing expert may be able to help you.

 

[OzWiz]

I know not the answer to such questions other than the noise is coming from the mixer valve itself.

I can see no names or numbers on the shower head to aid identification. It has 3 spray pattern settings. Does that help? I doubt it....

I was hoping everyone would just say "It's the ..." and it would all be simple...

We seem to have more pressure since the new combi was fitted but i have no way of measuring it...

 

[Sidewinder]

OK Oz,

The noise is from the mixer v/v.

Have you tried it with the hose to the shower head removed or with another hose, or without the shower head.

Can you try all 3 (?) and let us know the results?

 

[OzWiz]

Ok, I have had a fiddle with it in the shower tonight tried running it without the hose and without the shower head and no difference.

if i push against the front of the mixer unit (which is the temp control) the noise stops, but starts again when i take the pressure off...

I don't know if it'll help but i have attached a pic of the offending unit.

Where i come from we have a hot tap and a cold tap (we are simple folk).

 

[stani]

has the noise started since you had the combi installed?

 

[Sidewinder]

Missed the new boiler bit in the OP,but, is it a combi?

Right, it IS the mixer valve that is the problem IMHO.

Now, how you fix it depends on how good you are at plumbery!

I would suggest stripping and inspecting, you could have loose parts or damaged seals.

I can't message you through that too complex.

HOWEVER, when I have come across hydraulic systems exhibiting similar behaviour then careful internal inspection of the components of the offending valve has offered an answer.

 

[OzWiz]

It was doing it with the old boiler but has gotten far worse since the new one. There seems to be more pressure on the hot with the new boiler...

 

[Sidewinder]

Ahh, now then is it a combi, rather than a gravity fed, or have you gone for pumped hot water?

 

[stani]

was the old boiler a combi or a conventional type with a hot water cylinder?

 

[Sidewinder]

I thought that was about what had already been asked!

 

[OzWiz]

It's a combi, it's a combi, it's a combi!!!

 

[Sidewinder]

OK, so what was there before?

A combi will have mains hot water pressure.

Was this the situation prior to the new boiler?

 

[jl-heating]

i would just swop it, grohe are over rated pick up a tritan or similar unit and away you go, failing that ring the manufacturers or mail there support..

if it was a mira i would swop the cartridge

 

[OzWiz]

Thanks everyone,

It was an old Alpha combi which was causing us loads of hassle. Landlord had it changed to a new Ideal combi. Apologies if i've been a bit vague. There does seem to be more pressure since the swap tho.

Was hoping it was something simple as i didn't want to go to the landlord again so soon after the expense of a new boiler. I shall have to get her involved, i'm not keen on the idea of taking it apart myself, we'll end up having baths for weeks!

Cheers all,

 

[jl-heating]

oh dear ... alphas are terrible .. ideals are worse .