Sheepsplitter

I have a Potterton combi boiler installed.
It's about 12 years old.
My shower has stopped getting hot water, unless I turn it down to a trickle, which is useless.
I've got plenty of hot water in the taps in the bathroom and kitchen though.

Was wondering what likely causes could be.
Is it likely to be a problem with the shower - maybe a valve or seal gone?
Or could it be the boiler itself?
I did some web searches and found a thing called a diverter, which might be 'failing' to divert water to the correct location.

Any plumber types out there can give me a bit of advice?
Alternatively anyone live in Woking area can recommend a plumber that can look at it.
Thanks in advance.

davegtt

presuming the shower is electric? if so its likely to be the shower, especially if your getting hot water through the taps.

OllyK

Is it a thermostatic shower? If the hot water flow is poor then it will regulate the flow to keep the temperature constant.

It sounds a bit like you may have furring in the pipes causing an issue, but I am suprised on the shower seems affected. Check all the valves etc you can get to on the shower, it may be that something is blocking the flow, some crud broken away, or it could even be in the shower head etc. Do you get a good flow on cold? If so it will be the hot supply somewhere down the line

davegtt

Sounds like the heating element in the shower has gone to me. cant warm up enough water, hence it'll warm up a little water but wont warm up much

OllyK

I was assuming direct plumbed from the combi boiler!!

SJ_Skyline

Broken pump will have a similar effect..

MJW

If you still have hot water & heating it's unlikely to be a problem with the boiler.

Reality

Get's my vote too.

Open up the cover of the shower and hit the contents with a big hammer.

Will make you feel better.

ps Turn off the Electricity before attempting this "repair"

Alternatively - get the Plumber in

Sheepsplitter

Thanks for all the tips.
The shower is not electric, just uses the combi boiler and the pump on the boiler.
Free flowing cold is strong from the shower head.

T4molie

SS,

I don't think it's your Divertor Valve I've got that problem with my Combi at the moment - am waiting for the plumber to get a new one cos out of all the make / models available to buy my house had to have the one that had non std replacement plarts (just over a week waiting now )

The Divertor Valve will either work or not.... when you switch on the shower / hot water tap it opens up the flow which basically makes a rubber diaphragm in the DV move - this hits a switch which tells the boiler to start heating up the water. So if you're getting some warm water through then it's probably more of a pressure problem, cr@p in the pipes or knackered pump

HTH

Andy

B4 Boy (at work!)

The first question should be...

Is it only the shower that is affected?

If so I would suggest the thermostatic cartridge has failed or scaled up.

Aqualisa showers have two different types of cartridge a grey one and a pink one I think the grey is automatic type and the pink is manual only normally we use grey (about £66 trade from memory).

Trevi use gear sets as well as cartridges if you give ideal standard technical a call you can normally talk yourself into getting replacement parts for free.

Mira cartridges are approx £90 trade.

let me know shower make i might be able to assist.

Matt

davegtt

reading his original post it seems it is only the shower effected, and if you read the replies you'll know he aint got an electy shower.... good answer though as thats what I presumed to be at fault at first lol

B4 Boy (at work!)

Err thanks for the schooling!

If it is only the shower that is affected then it is reasonable to assume that the boiler is not at fault especially if it's supplying h/w services to the other outlets without problems. It wont be a pump problem as you cant add a pump to a combi system (you cant pump mains water)

Out of interest is Woking a hard water area and has water pressure in your kitchen cold tap decreased over the last 3 months?

Matt

Sheepsplitter

B4 Boy (at work!) : Only the shower is affected.
Done some further experimentation.
I took the shower rose off (need a new one anyway).
When I run the shower at anything up to 3/4 hot I can get it to fire up the boiler. (With the rose on it won't fire at all).
Above 3/4 it cuts out and water goes cold.
Not sure of the shower manufacturer, but it has a T logo on it made out of dots if that means anything?
Woking area is fairly hard water, and things do fur up.
Pressure in kitchen tap doesn't appear to have dropped off, but I've not been in the house much lately.

Any of this make sense?
Thanks for your help.

B4 Boy (at work!)

Hmmm... That may change things!

Sounds like there is a flow problem rather than the shower failing. It sounds like the hot water is not getting to the shower quick enough (either scale/furring in pipe-work) so its sitting around longer in the boiler and the boiler then thinks its up to temperature hence the boiler cutting out.

Have spoken briefly with a colleague regarding this, has suggested getting a larger shower rose to help with flow although this will only resolve the problem short term as there is quite possibly scale build up somewhere in the system that will get worse with the decreased flow.

It's definately worth getting a local plumber round to have a look they should be able to identify the problem pretty quickly it can only be a couple of things.

The shower definately sounds like a Trevi shower if thats any help.

Matt

Sheepsplitter

B4 Boy (at work!) :
What excellent help you've been.
Thanks.

I've requested a plumber and he's coming around on Friday.
I'm going to get a new shower head, but my local DIY shop only seems to have screw in units with the thread on the outside of hte head. My unit has a thread on the inside of the head, so will have to go to a specialist I guess.

Even with the head completely off the boiler stops when going >3/4 hot, so I'm puzzled as to why this happens.

Is there anything I can do to try and shift the scale/blockage?
i.e running it for an hour or so on hot, or something?

So I have a Trevi I guess :-)
Thanks