I have a combi boiler which is becoming erratic - hot water downstairs is okay but the upstairs shower doesn't always trigger the hot water demand. When that happens I've been turning on the downstairs hot tap first, then the shower and once it's heated up, slowly turning off the downstairs one. Sometimes the boiler stays on, sometimes it doesn't. I wondered if it was the shower thermostat but it does happen from time to time with the bath (which is separate), although not as often. The mains pressure and the boiler pressure are okay and so is the central heating. Is it more likely a boiler problem or could it be a pipe problem? Thanks.
Is there an obvious explanation to boiler problem?
- Thread starter SJRSJR
- Start date
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Make and model of combi would be a help. Just saying combi is no use at all.
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I suspect this is an older combi and that the water flow detection system is ailing. If so then I have been driving the part around London today!
Good fun these puzzles, much more vague and fun then the Times crossword!
Tony
Good fun these puzzles, much more vague and fun then the Times crossword!
Tony
Thanks for the replies, very helpfiul.
The boiler is an Ideal Combi Logic 35.
It was a new replacement boiler when we moved in nearly 3 years ago.
The cold water is mains fed.
Flow rate - approx 13 l/m on cold, 11/m on hot
No flow regulator
Isolating valves are fully open
Teatime said
So is that likely to be the problem - maybe there's crud inside the cartridge and it's time for a new cartridge (and a service pack for the strainers by the look of it?)
The boiler is an Ideal Combi Logic 35.
It was a new replacement boiler when we moved in nearly 3 years ago.
The cold water is mains fed.
Flow rate - approx 13 l/m on cold, 11/m on hot
No flow regulator
Isolating valves are fully open
Teatime said
That's new to me. I found the Installation and User Guide on the Mira website and removed the shower cartridge and there isn't one (hot or cold) I can see where they're meant to go but there's nothing there.
So is that likely to be the problem - maybe there's crud inside the cartridge and it's time for a new cartridge (and a service pack for the strainers by the look of it?)
Approx 9 l/m. Doesn't look or feel like there's anything restricting it, it's quite powerful.
I've just removed the cartridge and turned the water back on to let it flow freely out of the pipes. I don't want to keep doing it because water may get behind the tiles but out of the 3 times I tried it, the boiler only fired up once. So would that suggest it's not a shower problem and it's back to looking at the boiler /pipes?
I've just removed the cartridge and turned the water back on to let it flow freely out of the pipes. I don't want to keep doing it because water may get behind the tiles but out of the 3 times I tried it, the boiler only fired up once. So would that suggest it's not a shower problem and it's back to looking at the boiler /pipes?
Flow turbine is a common fault on these, without seeing/testing its what I'd put my money on 
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