Vaillant 824/2e tepid hot water

[strawbs]

Hope someone can help me with this problem.

I have a Vaillant 824/2e (about 8 yrs old), when hot water is demanded it goes warm to luke warm, warm to luke warm etc it never gets hot, even on the highest water temp setting.

It seems to be the same whether the CH is on or off at the time.

I'm not sure if this other issue is related, but the pressure was low on the boiler about 0.2 bar, so I added mains cold water using the key (while the CH was off) until it reached 1 bar pressure. Now since the 1st use of CH after that the pressure has gone up and stayed at almost 3 bar even when the CH and HW are off.

The central heating seems to work fine.

Hoping these may be symptons of the same problem, or my incompitence, not sure which!

Any advice would be appreciated. From looking through the forum, a sticky diverter valve has been mentioned...

Hope you can help.

 

[Agile]

If it was the diverter valve the rads would get hot when you use hot water.

You have a blocked plate heat exchanger!

It sounds as if you did not properly turn off the filling valves!

Or if its only when the boiler is hot then the expansion vessel is failed or discharged but thats unusual on your model.

Tony

 

[strawbs]

Thanks Tony for your reply.

I'm fairly sure the valves were closed after filling the water, it did not continue filling afterwards, only when the heating clicked on several hours later but I'll check it again.

Sounds like I'm better off getting a CORGI guy out, to check it over. Is it an easy thing to fix?

Thanks

Jon

 

[Agile]

Brain surgery is easy for a brain surgeon but I would be too frightened to start the job!

But I can diagnose faults on boilers and fix them but the surgeon has to call me to do it for him!

Tony