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Original poster

Hot water playing up.. help!

14 replies

Talkthirtytome · 27/11/2019 22:55

We have an old combi boiler (LPG gas) we had been out the other day so the heating wasn’t on. I went to run a bath, water cold. I realised after an hour of having the heating on, the water warmed up.
I’m trying to run a bath now after having the heating on 30 degrees for about 2 hours, and the water runs cold - then from somewhere (no idea where, the radiator maybe?) in the bathroom, there is some clicking noises, the water then gets hot for around a minute. Then it runs cold again!
Any ideas? No doubt it going to be something costly

OP posts:

PigletJohn · 27/11/2019 23:26

you haven't got a hot water cylinder as you have a combi, so fill a bucket from the hot bath tap, time it, caculate how many litres per minute you get. It should be around 12.

when you are running a bath, it should stop heating the radiators, but in the 5-10 minutes it takes, they should not have time to get cold.

if the boiler doesn't detect that you have turned the hot tap on, and start warming the tapwater, it is probably a fault in the boiler which needs professional attention.

hot water cylinders work differently.

Original poster

Talkthirtytome · 27/11/2019 23:36

Hi @Piglet - me again and my house of horrors! You came to my rescue last time.
The bath tap has always been so slow since we moved in, I have no idea why.
I ran it for around 10 minutes if not more and the bath was maybe half full and the water was just about the right temp to get in, probably on the cooler side.
It just seems to start of cold, then after about 30 seconds I hear this clicking, I get another 30 seconds or so of hot water and then it cools off again.
As I say we only get any kind of hot water at all if the radiators have been on, which is very odd.
Could it be a diverter valve?

OP posts:

PigletJohn · 28/11/2019 00:23

still need to know the number of litres per minute from the hot bathtap.

Original poster

Talkthirtytome · 28/11/2019 01:22

Roughly 5 and a half litres per minute. What does that mean?

OP posts:

PigletJohn · 28/11/2019 09:32

It's unusually low for a combi. It might be insufficient to operate the flow switch. Has it always been that bad?

The fact that hw seems to be hotter once all the radiators are hot suggests your diverter valve is not working properly.

Either way, you are going to need a boiler mender.

Original poster

Talkthirtytome · 28/11/2019 10:57

@PigletJohn we have been in this house 18 months and the bath has always taken forever to run so I think it must have always been this low, although I think it has got worse recently.
Am I better looking for a plumber or a boiler man? x

OP posts:

PigletJohn · 28/11/2019 11:03

Boiler man (Gas Safe accredited for LPG boilers)

Original poster

Talkthirtytome · 28/11/2019 13:25

@PigletJohn got somebody out. He said it could be some kind of electrical wire that tells the heating and hot water where to go? So we’re trying replacing that as it’s only £100. But he said it looks like there is a leak in the system somewhere also. I think it’s going to end up being a big job of locating this mystery leak and a new boiler in the end. As it is about 18 years old.

OP posts:

PigletJohn · 28/11/2019 13:34

if it's a combi, I don't think the diverter valve will be capable of intentionally sending heat to radiators and hot tapwater at the same time, I think it's more likely wear in the valve. The idea of a leak between DHW and CH sounds feasible and might be rather costly

Is he experienced in your particular model of boiler?

A heat-only boiler with a cylinder can behave in that way, but, again, it's usually the 3-port valve at fault, less likely to be a wiring error.

Arnoldthecat · 28/11/2019 13:40

Bring back the space saver..

Original poster

Talkthirtytome · 28/11/2019 13:41

He didn’t say he thought it was the diverter valve, he said it’s some kind of electrical pipe that tells the water where to go? (I’m sorry I’m terrible at understanding these things)
I’m sure whatever it is will cost us a fortune at it always seems to with this house. He said the same as you did about the radiators going off when the taps are on but not noticing it as they don’t have time to cool.
He wasn’t personally experienced but he rang someone who was specialist in artistan boilers which is who suggested it could be this wire/pipe.
I honestly think we’re going to end up habits to spend a fortune to find this leak and on a new boiler in the long run

OP posts:

Original poster

Talkthirtytome · 28/11/2019 13:41

This is it

OP posts:

PigletJohn · 28/11/2019 13:51

'mmm

Ariston don't have a very good reputation. I fear you need to be shaking your piggy bank and bracing yourself for bad news.

Original poster

Talkthirtytome · 29/11/2019 22:35

@PigletJohn oh really I think that everything that was installed in this house when it was built was done on the cheap so it doesn’t surprise me. I have found it we put the boiler in that flue override mode again we do get perfect hot water so at least it’s a short term solution to be able to bath my little one until the plumber comes back next week.

OP posts:

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