Worcester combi boiler doesn't always "start first time"

[Jonny_]

Now and then my combi boiler - a Worcester 24i of approx. 2004 vintage - fails to produce any hot water when the hot tap is opened (it usually goes from stone cold to hot within about 20 secs); however, if this happens, shutting the tap off then on again is enough to bring it to life.

It's not a major problem (I've lived with it for ~2 years) but was wondering if anyone here has had similar experiences (for all I know this could be a common fault) or knows owt about the inner workings of these things? If it's an easy and cheap fix then I'll have a bash at fixing it, otherwise it's getting ignored until the thing dies completely!

(Tried Googling but got fed up trawling through hordes of ste, irrelevant, useless webpages which more often than not seem to be peddling some toss or other that I don't want to waste money on!)

[Phooey]

Yep, mine does this too, luckily not too often - can be a pain in the a$$ when you are waiting for the shower to warm up though. My combi is 10 years old and has been doing this for approx 3-4 months, we are on a WorcesterBosch yearly maintenance plan which includes a service, so will mention it next service (September)

I would be interested to hear the reason why it does this too

[johnthegas]

There's a flow switch in the hot water circuit mate, it sounds like it is sticking from time to time. No major biggie to change.
John.

[homeimprovements]

As above flow switch is sticking. Not a expensive job to get fixed and parts readily available

Cheers