Problem with shower/taps going hot and cold

[SADavids]

Hi,
I'm literally ripping my hair out of frustration, not good on Christmas Eve

The shower at my parents isn't working properly, the hot water tap fluctuates between hot to cold (utterly frustrating because the whole family is back for Christmas). I thought my old man was sorting it but for some reason it became a really complicated issue.

From my Dad's account:

We had an Eon engineer out to look at our combi-boiler, he seems to think the issue is to do with the thermostat inside the electric shower? Therefore, it is a shower issue and we need a new one. Fair enough.

Then we called a local plumber who kindly came around, said it was a 'plate to plate heat exchange' issue, therefore, it's something to do with the boiler. He told my Dad what parts were needed. Ok?

We rang Eon and they sent another engineer out to check our water, again he said it's nothing to do with the boiler, it's to do with the shower.

...

We can't fix the problem because no-one is able to pinpoint what it is. Is it the boiler or the shower?! I decided to get a grip of this and try to get the darn shower fixed.

Apparently, the plumber said that, if all the taps in the house go from hot to cold - it means the problem stems from the boiler. And my Dad said the Eon engineer tested the running water in the kitchen for a long time and said it was fine. I don't know whether the time of day might affect anything because the Eon guy tested at 9am in the morning, we seem to have the issue in the evenings.

We know the temperature fluctuates on all the taps, so I don't really understand what is going on. I've attached some photos of the boiler and shower setup - sorry, I actually don't know what make the shower is, my parents can't remember.

Any help or directions is much appreciated, I keep seeing the problem but no solutions Do we need a part for the combi boiler or the whole shower replacing? I'm fine with either one... I just want it sorted.

Thank you and Merry Christmas.

 

[HERTS P&D]

If it happens on all taps then it's the boiler, if it only happens on the shower then a new thermostatic cartridge is needed.

Andy

 

[Terry7556]

new shower hose would,nt do no harm either

 

[SADavids]

Yeh, I'll make a trip to B&Q sometime to buy them a new hose!

As for the problem - is it likely two engineers from Eon didn't diagnose our problem properly?

The plumber said it's the boiler, they say it's the shower.

 

[twgas]

I would suspect the plate h/ex is partially blocked, looks like cheapest possible instal - no flush = dirt in boiler and this issue recurring time after time.

 

[dcawkwell]

Well it's a ferroli boiler for a start so not good.

Turn the kitchen tap with the equivalent flow that you think the shower
would be using and let it run. If the hot water fluctuates in temperature
and the boiler is shutting down and then firing up during this
it is the plate heat exchanger in the boiler.

It is easy to clean out the heat exchanger in the boiler
and a new thermostatic valve for the shower is also relatively
cheap. Easy to sort this out.

 

[Terry7556]

that looks like a f series ,
my lad has a 14 year old domina that i keep an eye on. the hot water performance is a lot better than many of the modern combis i see
go to screwfix, new hose less than a fiver and carry out the tests described above. eliminate the hose first and any problems that it causes ie blocked head
Not the main fault, that's in the boiler but that hose is contributing to your problems

 

[SADavids]

Thank you!

I'll get a new hose first.
Then I'll do the testing with the tap.


I don't think my Dad understood much when the engineers came, I don't live here anymore, so I'm trying to fix this before I leave again.

I will let you know how it goes. Thanks again.

 

[Whitespirit66]

This all seems to have got very complicated for such an easy problem to diagnose. It appears that access is available to the pipes running to the back of the shower valve. Feel the hot supply pipe into shower. If it goes hot and cold at the same time as the water coming out of the shower does, it's the boiler - poss plate hex. Or, you could feel the hot pipe out of boiler whilst shower running. If the hot pipe remains constant temp, it's likely to be shower fault.

P.S. If your parents' plumber is responsible for the pipework, look for another plumber.

 

[SADavids]

Is the pipework badly done? I do wonder because my Dad's a bit of a tightwad, he probably got it done as cheaply as possible...



Is it worth getting an electric one installed? I'm thinking long-term.

 

[Terry7556]

i have an electric shower in my home because it an alternative if the boiler or other shower is down
since i owned my home ive never had a boiler let me down so not sure of the logic behind that
having said that i look after my stuff and maintain it
electric shower will feel pizz poor compared to your present one and it costs more to heat water by electricity
would never guessed your dad was careful with money looking at that shower hose

 

[Whitespirit66]

Is the pipework badly done? .

No doubt it's functional. Just looks a real amateur hotchpotch of copper and plastic pipe, plus plastic, soldered and compression joints. The Ferollii boiler is the icing on the cake. I'm thinking it's a DIY job - the white PTFE on the compression joints is a dead giveaway. My point was, if your father actually paid for this work, I would look elsewhere for plumbers in future.

Is it worth getting an electric one installed? I'm thinking long-term.

No. Electric showers don't give a good flow of water and are expensive to run. When the fault is rectified, stick with this type of setup. The only good thing about an electric shower, is when the Ferolli boiler breaks down, you still have a shower.

 

[Jackrae]

His sparky wasn't too clever either, mounting the boiler isolator right under a pipe fitting

 

[SADavids]

Installed a lovely new £30 hose from B&Q. The old one was actually taped at both ends!




I ran the shower and we tested the hot water pipe behind it, the temperature fluctuated on the pipe. That means it's the Plate heat exchanger right?

During the test my Dad said his Eon Central Heating Care package didn't cover 'Plate Heat Exchanger' and it's £300 to fix it...



I didn't know this. I mean, if he knew it'd take £300 to fix it - that implies the Eon engineer would have given him that quote! I asked him for the Terms and conditions and I'm sifting through that booklet now. He could have told me this a few days ago! What exactly is a plate heat exchanger? If it's part of the boiler, I can't see why Eon Central Heating Care package won't cover it?

==========


The boiler is a Ferroli F 30 (just found the missing lid in the garage!)

I googled and found a PDF manual. I can't make heads or tails out of the schematic!



If it IS the plate h/ex, is it easy enough to do it myself? Am I better off getting an Eon engineer back or just call a local plumber to sort it out for us?

More importantly, is £300 a fair quote?



Thanks guys!

 

[SADavids]

No doubt it's functional. Just looks a real amateur hotchpotch of copper and plastic pipe, plus plastic, soldered and compression joints. The Ferollii boiler is the icing on the cake. I'm thinking it's a DIY job - the white PTFE on the compression joints is a dead giveaway. My point was, if your father actually paid for this work, I would look elsewhere for plumbers in future.

Aye, he paid. Bet it was the cheapest plumber he could find? Or he told the plumber to do it at the cheapest price?