Vaillant 242 Turbomax hot water intermittent

[primetime]

The hot water for the shower doesn't always come on but is ok for the other hot water taps - basin and kitchen sink. The shower has the lowest flow rate.
I suspected the diverter valve diaphragm but there were no splits or tears. I replaced the diaphragm and everything else that came in the diverter service kit. The hot water seemed ok for a few days but has gone back to being intermittent.
The microswitch doesn't seem to operate the times the DHW doesn't come on despite re-adjustment.
The Central Heating radiator supply pipe also gets warm for a little way (heating not on) when the DHW runs for a little while.
Replacement of entire diverter required?

 

[hertsboilers]

Yes, whole valve time.

 

[Bunnyman]

Yes 011289 is what u need

 

[primetime]

Thanks. I had another go at adjusting the microswitch. Seems ok for now.

 

[hertsboilers]

Thanks. I had another go at adjusting the microswitch. Seems ok for now.

So you will still get warm radiators when you fill your bath.

 

[primetime]

Rads not getting warm, just a short section of the supply from the diverter.

 

[Bunnyman]

Well you asked for advice mate, just change the valve, i know its expensive but u will do the same as many professionals, fanny around convincing urself it seems ok, the problem is there

 

[primetime]

I appreciate the advice. I got to the same conclusion but wanted to hear it from someone with more experience or if there something else that could be done. Not saying I won't replace it but in no rush just yet. Have sourced a new diverter assembly. Thanks again.

 

[Agile]

I have successfully adjusted the switch in a few cases. But I also agree that on that model its better replacing the whole valve.

Tony

 

[AGAS]

I appreciate the advice. I got to the same conclusion but wanted to hear it from someone with more experience or if there something else that could be done. Not saying I won't replace it but in no rush just yet. Have sourced a new diverter assembly. Thanks again.

don't be like some wally's on here who don't take the advice from someone who knows what their talking about with vaillants ( bunnyman ) , because if you go the cheap way you will only spend ( cost & money ) much more in the end .

there are plenty of examples on this forum