I have a Europa (Ideal Caradon) Combi wall-hung gas boiler. Perhaps a couple
of months ago I noticed that the DHW flow to the kitchen tap (nearest to
boiler) was getting low (approx half normal flow). As the DHW taps to
shower/ bathroom were still working normally I checked the tap for a
blockage, and considered replacing the pipework to the tap from where it
tees off from the HW feed to the bathroom. But then I noticed a problem with
the boiler - the thermostat settings are no longer graduated - i.e. the
setting is either warm (minimum?) or very hot (maximum) with no in between
on the dial ('very hot' kicks in around halfway on the dial). When on a warm
setting the pressure stays relatively low - from 1.5bar cold to perhaps
2.5bar when in use - and relights in the morning when off overnight. But
when the system is on a 'very hot' setting the pressure goes right up to
nearly 4bar when in use, but overnight the pressure goes back down below
1bar so the boiler doesn't ignite in the morning.
Any thoughts before I start delving...?

Thanks
Gilbert

"Gilbert" wrote in message
...
I have a Europa (Ideal Caradon) Combi wall-hung gas boiler. Perhaps a
couple of months ago I noticed that the DHW flow to the kitchen tap
(nearest to boiler) was getting low (approx half normal flow). As the DHW
taps to shower/ bathroom were still working normally I checked the tap for
a blockage, and considered replacing the pipework to the tap from where it
tees off from the HW feed to the bathroom. But then I noticed a problem
with the boiler - the thermostat settings are no longer graduated - i.e.
the setting is either warm (minimum?) or very hot (maximum) with no in
between on the dial ('very hot' kicks in around halfway on the dial). When
on a warm setting the pressure stays relatively low - from 1.5bar cold to
perhaps 2.5bar when in use - and relights in the morning when off
overnight. But when the system is on a 'very hot' setting the pressure goes
right up to nearly 4bar when in use, but overnight the pressure goes back
down below 1bar so the boiler doesn't ignite in the morning.
Any thoughts before I start delving...?

Thanks
Gilbert

The pressure relates to the sealed part of the system and will rise as the
water in the sealed system gets hotter. It will not have any effect on the
tap. Are you sure that the tap was checked thoroughly. Is it a conventional
one or a ceramic disc one?

"John" wrote

The pressure relates to the sealed part of the system and will rise as the
water in the sealed system gets hotter. It will not have any effect on the
tap. Are you sure that the tap was checked thoroughly. Is it a
conventional one or a ceramic disc one?

Yes, I realise that the system is sealed, I was just pointing out that the
pressure rise had deviated from the norm recently and wondered if anyone had
witnessed anything similar. I expect that the tap/boiler problems are almost
certainly unconnected, but you never know!
I checked the tap - a monobloc ceramic disc - and it seems in good order. Of
course, I could be mistaken - perhaps I'll swap over the flexible H/C
connections and see if that makes a difference. But my real interest lies
with the boiler problem.

Cheers
Gilbert

Gilbert wrote:

I have a Europa (Ideal Caradon) Combi wall-hung gas boiler. Perhaps a couple
of months ago I noticed that the DHW flow to the kitchen tap (nearest to
boiler) was getting low (approx half normal flow). As the DHW taps to
shower/ bathroom were still working normally I checked the tap for a
blockage, and considered replacing the pipework to the tap from where it
tees off from the HW feed to the bathroom. But then I noticed a problem with
the boiler - the thermostat settings are no longer graduated - i.e. the
setting is either warm (minimum?) or very hot (maximum) with no in between
on the dial ('very hot' kicks in around halfway on the dial). When on a warm
setting the pressure stays relatively low - from 1.5bar cold to perhaps
2.5bar when in use - and relights in the morning when off overnight. But
when the system is on a 'very hot' setting the pressure goes right up to
nearly 4bar when in use, but overnight the pressure goes back down below
1bar so the boiler doesn't ignite in the morning.
Any thoughts before I start delving...?

It sounds as if you may have two unrelated problems. The issue with
regard to the system pressure rising too high sounds like lack of
expansion room. The classic cause of this is the expansion vessel having
either failed or at least being in need of pumping up.

This is all covered in detail he

http://www.makewrite.demon.co.uk/SealedCH.html

The issue with the tap flow rate could be a number of problems. You did
not mention where in the country you were or how hard the local water
is, but one common problem that can lead to issues like this is the
build up of scale in the plate heat exchanger that heats the hot water.

--
Cheers,

John.

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In message , Gilbert
writes
I have a Europa (Ideal Caradon) Combi wall-hung gas boiler. Perhaps a couple
of months ago I noticed that the DHW flow to the kitchen tap (nearest to
boiler) was getting low (approx half normal flow). As the DHW taps to
shower/ bathroom were still working normally I checked the tap for a
blockage, and considered replacing the pipework to the tap from where it
tees off from the HW feed to the bathroom.

We're in a hard water area and had exactly this problem, it was due to
lime scale in the corrugated flexible tail feeding the tap, cured by
emptying the water out of the hot pipework and pouring in lime scale
remover.


--
bof at bof dot me dot uk

"bof" wrote

We're in a hard water area and had exactly this problem, it was due to
lime scale in the corrugated flexible tail feeding the tap, cured by
emptying the water out of the hot pipework and pouring in lime scale
remover.

Thanks for that. I'll definitely check the flexible pipe for scale.
Cheers
Gilbert