Vaillant combi without HW

[hudster]

Hi, I have a Vaillant 831 combi. Earlier today I installed some new taps in the downstairs loo, there were no isolating values so I had turn off the stopcock and drain both hot and cold feeds down. Taps fitted and everything's good.

However, we now have no hot water. The Vaillant is running CH fine (just as well in this weather!) but does not detect the demand for HW. No error message is displayed, nothing seems to indicate there is a problem.

I have discovered that I can get permanent luke warm water by enabling the Warmstart feature. Presumably the combi is failing to detect demand and just ticking over due to Warmstart.

I've tried resetting the boiler but no change.

Any advice as to what this could be please?

I'm unclear as to whether draining the system may have caused this problem, but I've flushed all air out of the system now.

 

[hudster]

Any ideas please?

I may have to call a plumber

 

[ianmcd]

if water is coming out of the hot tap but the boiler is not detecting it then you may have forced some grit from the water pipe into the impellor sensor in the boiler

 

[hudster]

Any way I can confirm/fix this myself? Would flushing clean water back through the boiler be likely to help?

 

[ianmcd]

not really Im afraid, but if you wait a bit there are usually Valliant lads that come on here most evenings and they might know a quick fix

 

[Agile]

No quick fix apart from removing and cleaning or replacing the sensor!

Tony

 

[hudster]

Thanks to those who replied

Blocked impeller was the correct answer

 

[joe-90]

Now this thread has finished can I just ask a question? If a bathroom fitter had changed the taps and this had happened - whose fault would it be?

 

[Whitespirit66]

Now this thread has finished can I just ask a question? If a bathroom fitter had changed the taps and this had happened - whose fault would it be?

Bored with the Gen. Discussion forum these days are we?

 

[joe-90]

Yes. I feel wanted and needed here.