Irregular domestic hot water supply

[greenrook]

We have a Saunier Duval combi boiler, about 4 years old. From time to time, when a hot tap is turned on, the boiler doesn't fire, consequently no hot water. This usually happens after a prolonged spell of using the hot water, and after a 'resting' period, the hot water will function again. I suspect the the domestic hot water microswitch, and since we have a full house at Christmas, I just KNOW the bloody thing will pack up then. I wonder about the mains water pressure, any advice anyone??

[gasman]

Get it serviced it sounds like the diagphram is on its way out on the DHW flow switch. I doubt very much that the water pressure is too low as the water companies have to by law provide at least 1 Bar

[greenrook]

Hello gasman, just wanted corroboration, I thought it must be the flowswitch. I think I'll just get the new switch from my local Plumbase and keep it by me, then if push comes to shove (probably on Christmas Day!) I'll amuse myself with a big whisky in one hand and the relevant tools in the other. It doesn't look much of a job - you may have gathered I'm a very long ago retired plumber, last time I held a Corgi cert was over 13 years ago. I appreciate your prompt help, and I hope I can call on you again when I'm in trouble

[gasman]

Good luck greenrook and a merry christmas to you.

[greenrook]

and you, gasman