New Shower with reduced flow

[Dexman]

Hi

I put in a new thermostatic mixer shower to replace my old mixer shower as it wouldn't work with my new combi. When I turn the shower on, the water comes out at a good pressure and then drops down to a more reduced pressure after a few seconds. It may sound strange but the flow seems to pulsate as opposed to flowing normally. Could it be a case of an air pocket somewhere ?

Any help greatly appreciated as I haven't got a clue what to do.

Thanks

 

[corgiman]

make sure the shower head of you new shower doew not have a PULSE setting (minre has and its lovely ) that would explain the pulsing may even explain the pressure prob an all

 

[Dexman]

I have checked and it doesn't have a pulse setting. It seems to be a restricted flow of water. If you listen to the feeder pipes it doesn't sound like it's free flowing atall more intermittent bursts of pressure. I have tried running just hot and then just cold to see if there is anything to clear but it hasn't done any good.

 

[corgiman]

what the pressure like at the other taps??

 

[Dexman]

The tap pressure in the bath and sink are fine as is the kitchen.

 

[ChrisR]

Usually those symptoms are of a kinked shower hose (liner).

Otherwise the mixer is reducing the hot flow to get the water cooler, the combis water therefore comes out hotter, and the situation gets worse until the combi turns off. Sometimes turning on the bathroom basin hot tap helps. SOurce of that problem is that the combi can't adequately regulate temp at low flows.

I no longer fit cheap tstatic valves onto cheap combis - or even dear ones come to that!

 

[corgiman]

Agree with chris

Except high recommend the GROHE avansys shower valve. Fitted loads and loads on combis not one complaint

 

[ChrisR]

Fine, that isn't a CHEAP valve!! It's the likes of scroofix, wix, and others well under £100 which seem to give problems. Old combis, too.

 

[corgiman]

woo chris, bit grumpy this fine morning aint you, mind you know what you mean hate mondays my self especially when someone is late for an appointment

you did say that you would not fit an expensive valve you know

in fact you were saying that you would not fit any type of thermostatic valve so I was just giving you an opinion as to what is a perfect combi shower.

not that dear either 150 plus vat for shower valve

 

[ChrisR]

No, no grumpier than normal!
By
"I no longer fit cheap tstatic valves onto cheap combis - or even dear ones come to that!"

I meant i don't fit cheap thermostatic valves any more, to combis. Cheap combis seem to be less well regulated than dear ones , but "even dear ones" like Vaillants 242's, don't like cheap tstatic valves. You CAN get a thermostatic mixer for under £50. They are probably similar to the £80 - £100 ones from more respectable outlets.
Grohe, Hansgrohe, Aqualisa, Mira, no problems generally. Bristan are doing a newish cheapie I'm suspicious of.

As for "
you did say that you would not fit an expensive valve you know

in fact you were saying that you would not fit any type of thermostatic valve "
er, eh? Must admit recently I've not done posh enough bathrooms to warrant posh fittings, - ie basic rented places mostly, so I've avoided tstatic valves.

 

[corgiman]

Like the man in orthopedic shoes I stand corrected