Vaillant - TurboMax Pro 24E - Yellow light flashing problem

[hpmum]

Hello,
Am new to this site and need some good help - Please.

I have a Vaillant combi boiler and the ignition light (the one that looks like an egg-timer) is regularly flashing yellow.

I have to press reset and then it sometimes fires up immediately and then once again there is constant hot water & heating.
Other times I have to press reset a few times before it fires up again and stays constant yellow (rather than flashing).

It happened this time last year, which makes me think it is something to do with the cold weather ??

The manual says it could be that there is not enough water in the system. But there is. I have tried to add a bit of water, but then if I press reset, there is the most awful clunking sound and the pressure dial swings violently to the right (maximum), gets stuck, and only when I quickly turn off the boiler, does the dial then slowly fall back to where it was positioned before. It is quite a frightening sound. Makes me feel like the whole boiler is about to blow up or fall off the wall

Does anyone have some advice on what is happening ?
And what I need to do ?

The boiler was fitted in Dec 2000, so it is obviously not new.
It services only one bathroom, dishwasher, washing machine and kitchen.
I really need this boiler to be working properly.
Thanks in advance.

 

[Burnerman]

That indicator does tell you that there isn't enough water in the system, and I think what is happening is that when you refill, the pressure release valve is opening and then closing again - these can make one hell of a racket.
As the pressure shoots right up on the gauge, I think that the expansion vessel within the boiler is faulty....either there is no air pressure in it or the diaphragm seal between the two halves of this thing has split.
John

 

[Agile]

Its unusual for the EXVs to fail on vaillant boilers so you may be lucky and it might just need repressurising.

You can see how to do it in this site's FAQ but it MUST be done with the system open.

The obvious question is when did you last have the boiler serviced?

The failure to reliably ignite is totally seperate to the pressure issue and might just indicate a lack of proper servicing rather than anything failed as such.

Tony