Vailiant 242e - Hot Water Problem

[Ifti]

Hi,

we have has this bolier for around 5 years the water is medium not too hard and not too soft.

The problem we have is that sometimes when we put the hot water on the lights go up on after the other but as it tries to turn the flame on it cuts off, or sometimes it cuts off right after the green light and goes round and round again. it start ok somethimes but sometimes it doesnt.

we have had the diverter value changed, last year. the hot water demand light does come on and stay on until the boiler goes to the flame ingition light and then all the light go back down to the start.

The Central heating is fine.

The flame failiure light Does not come on at all.

for a bit of extra info its a vailiant 242e tubo max (i think) with the green nobs on a plastic panel.

another thing i must mention is that the water pressure drop slightly as the hot water comes on, is this normal or is this a fault too ?

any advice to fix the problem will be welcomed.

Please ask for any more info if nesscecary.

Thanks in advance to all.

 

[Ifti]

anyone know of a cause/solution

 

[chrishutt]

You need to look at the manual and the diagnostic lights on the control panel and try to follow the sequence of operations. Using the fault finding section of the manual should enable you to pin the problem down.

 

[Ifti]

just want to add onto this another slight problem, the hot water doesnt come on at all sometimes, we had the microswitch replaced some time ago does anyone know when i can get one from and how hard it is to fit

thanks in advance

 

[Gasguru]

Is the hot water demand light going off even though the hot tap is open?

Did they change just the lower section of the diverter?

Vaillant did have some rubbish diaphragms a while ago that only last a year or two before they become holed.

The microswitches are fairly reliable.

You could check to see if the switch operates when you turn on the hot tap. Sometimes the "bow" breaks. This is a tiny plastic lever that operates the microswitch.

It is normal for the pressure gauge to fluctuate as the pump kicks in.

 

[Agile]

As the boiler is actuated by a hot water demand the diverter should be OK.

It sounds like a system flow or a combustion problem.

As in all these cases when the fault is not obvious, I would have to advise that you may need to get a competent boiler engineer to diagnose the fault.

Tony Glazier