Vaillant VCW 242E hot water problem

[b0ne5ish]

Hi,

I have a Vaillant VCW 242E, when I switch on the hot water it heats for about 3-4 min's and then the water runs cold. If I switch the boiler off, then back on again and leave it for a while the water heats again for a few min's before running cold again.

Anyone have any idea what this might be?

Many Thanks,
Steve

 

[b0ne5ish]

Bump any Vaillant experts out there?

 

[Agile]

First thing to check visually is that the diverter valve DHW demand switch is remaining made.

Tony

 

[Andygasman2010]

We need to know exactly what it's doing when it's cut out. I don't think you need a Vaillant expert at this stage, just a little more info on what the boiler on what's going on at the time of the fault.