No hot water, Alpha CD24C

17 Jan 2009
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United Kingdom
Hi every one hope some one could help me.

I got a Alpha CD24C combi boiler, the problem is that i most often i dont get any hot water when turning the tap on.

Some times it starts and work fine, some times it cuts out after a while.

A couple off times, when a bit frustrated, i have given it a bit of a bash on the side and the hot water comes on and it ignites.

When i turn the central heating on as well then i get hot water.

Some times when leaving the tap running it comes to life and no problem.

Starting to find i a bit frustrating when the hot water cut out in the middle of an shower and need to go down stairs and turn the heating on with shampoo in the eyes.

The central heating is working fine and the boiler where installed two years ago.

Thanks a lot for taking your time reading this and hope some one can spend a few more minutes and help me with my problem.

TNX Wolfeye
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First thing to check and/or replace is the flow switch on top of the diverter valve.

Prise this carefully off and if the boiler fires up it is working ok. If the boiler doesn't fire it is this switch faulty. A very common problem with alphas.

If the switch is ok, then it sounds like the diaphragm has perished and needs changing.
TNX Dave!! Ii got off and gave the switch some massage (the little white ball, which i gently press in a couple off times) and put it back in it's place and it seems like it work fine at the moment.

Do i need to replace it, or do you think it will be fine

had some problem to find it at first but found this installation document help full.

How to remove casing Section 8:1 (2 Screws)

Flow switch Section 8:15

If any one has the same problem the flow switch is the black plastic clip, pressed around the brass Diverter valve.
You will need to pull and press the switch straight upwards as its a plastic peg going down in to the Diverter valve,
on the end off this peg it's a little white ball which senses the flow i guess,
it was this one i gave a couple off gentle pushes and the put it back in.

And it started working fine for me at the moment.

Thanks again dave!
usually they last a few days and your back to the same problem. i would change it.
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Changed one last week. Think the part was £42 + VAT retail, plus £70 + VAT for me to fit (call out etc)

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