That's the one we have, the CH timer went last year. I'll look forward to the valve going.When our 6 / 7 year old Vaillant ecotech plus did the same a few years ago I had to replace the motorised valve arrowed to sort it, I believe it is a common fault on them. May just be your photo angle but yours looks a bit different.
View attachment 262825
Pete
jamed pump there on that model
first thing to fire up is the central heating pump hence why your water goes colder on your therostat guage
then your second fan kicks in top right is the sound for it this is your igniter fan
then it fires up annd lights the gas like it does when on first vid
couldnt hear it this morning before work turned volume right up to hear it just now
you should really have that boiler serviced they have a massive problem on them
Surely since the pump services hot water and heating and I have hot water, it can’t be the pump. This particular model has the updated pump and I stuck my ear against it and it does spin until it inexplicably decides not to carry on.
When our 6 / 7 year old Vaillant ecotech plus did the same a few years ago I had to replace the motorised valve arrowed to sort it, I believe it is a common fault on them. May just be your photo angle but yours looks a bit different.
View attachment 262825
Pete
I have the 831 Pro, ostensibly the same boiler. Things to check.
Pressure vessel. Drain the boiler down (not the whole CH system) and check the pressure. Should be 0.75 bar. Adjust with a foot pump or similar. Then refill the system ensuring you bleed any air out of the pump.
Check the display brightness when the various valves are clicking, especially the gas valve. If there is any dimming of the backlighting the PCB is on it's way. Small transformer and a power FET will fix it. Can also be relays with burnt contacts.
Clean out the scale filter, or replace it with a new one. Bizarrely Vaillant don't see fit to protect the main H/E with a filter, only the HW exchanger. Not sure why.
If the pump is stopping that is a common fault on these. Vaillant service says check PCB first. then replace the pump. There are newer revisions of the pump which makes me wonder if any of the early ones had inherent issues. I think mine is u p to revision 3 now, so there were 2 which had issues.
EDIT. Just to add, if it is the PCB and you manage to buy a new one, you will need a code from Vaillant to make it work again. They only give out these codes to registered Gas Safe engineers.
pumps there for central heating not for hot water side of it
the flue pump will start up though
check your install stats on your instructions has a diagnoses at end to point roughly what it is
but ya dont have to believe me and i have a vailiant in the house and repaired your model who someone messed with casued more damage due to them messing around in there boiler
like you wont get it serviced and expect it to last years his lasted 14 years and melted the aluminium plate on the front that caused a fire within the boiler
This guy is good for reconditioned PCB 's if you need one. They're in Watford. CET.
https://www.cetltd.com/default.asp?let=pcb?let=pcb
Interesting link, thanks for posting. I had to replace the one in my Baxi the other year, I paid about £30 more back then for a brand new PCB so I'm not sure that's much of a saving to be honest.
Are all these PCB's not that great I'm wondering? Sure mine displayed a 'fan fault' code at first, I checked that and other associated components, all checked out fine so I took a punt on the board being faulty, boiler worked fine straight away after swapping that out.
Surely if you need to ask the internet indepth questions you should not be doing it
Surely if you need to ask the internet indepth questions you should not be doing it
I think it's more that these things are actually pretty complicated items. Water, fire, electricity all in the same spot. What could possibly go wrong?
The issue is compounded by people like me where I don't have it serviced regularly as I should. I just expect it to work and I don't make regular payments for servicing because I don't have a regular income.