Help and advice please. Help and information on all topics relating to your central heating, air conditioning and ventilation issues.

[mblago]

We're getting hot water into the rads when the DHW is turned on, even though I have got it on summer setting. We've had the diverter valve replaced only yesterday and the hot water seems fine but still getting hot water going to the rads..........any ideas what else it could be please ?

[htg engineer]

Boiler type ?

It's definately the diverter/ three port valve though - did he change the whole valve or just the head ?


htg

[mblago]

Its a Vaillant EcoTech Pro combi, I'm not sure what he replaced, says on the paperwork it was a diverter valve, the work was carried out by British Gas. The boiler is only 18 months old and only comes with one year guarantee.

[htg engineer]

BG have been and the problem is still there - get them back.

htg

[mblago]

BG have been back and replaced the diverter again but I am still having the same problem, the water sometimes gets properly hot but other times just luke warm and rads getting hot.They are now at a loss to what it could be, they are coming back again tomorrow for the 4th time. HTG engineer, have you any idea what else it could be at all please ?

[plumbbob]

I think I would check any external controls to be sure they a functioning and wired correctly.

Are the rads warm 24/7 or does the fault occur occasionally? When does it happen? What are the conditions when it happens? Does the boiler fire up when there is no call for hot water. Does it shut down as soon as the hot tap is turned off. Has it been like this from new?

To find obscure faults, every factor is important, and often even the smallest clue can help discover the answer.

[htg engineer]

What else can it be, the only thing that's different between running in CH and DHW is the position of the diverter.

The diverter either diverts the water around the boiler through the plate heat-ex or to the radiators, have you witnessed the diverter being changed ? or at least seen an old one ?

Is the whole valve being changed, sometimes people just change part of it ?

Have they also tried changing the motorised head ?


htg

[mblago]

Bt Gas have given up, they are now passing it over to a Vaillant engineer, I'll let you know the outcome. Thanks for your help guys.

[mblago]

The Vaillant engineer has been and gone and after scratching his head for a bit has changed the PCB after first changing some wiring.
It seems to have done the trick but as its an intermitent fault a bit too early to tell.

[htg engineer]

Let's hope that's sorted for you now.


htg