Vaillant Problem

[Shamus]

I have a Vaillant Boiler (VCW) that has suddenly stopped firing up when i put the hot taps on. To get hot water I have to put the CH on. At the Back Top Left i have located what i am sure is the flow switch for the DHW (MS1 in manual) which when pressed fires the boiler up. I would like to know if it would be ok to adjust the MS (midges D**k) or should i find out why the switch is not making the actuator. Will it be gung in my system? What is involved in a 'take out and lube' on this item. It looks straight forward in the manual to get the item out but how further would i need to go? Is the diaphram in the item? Can i check that while i'm at it?

kind regards
Shaun

 

[kevplumb]

how old is the boiler /do you have hars water ?

 

[Shamus]

The boiler I would guess to be at least 10 years old.
The water is not hard in the north of england.

regards
Shamus

 

[ChrisR]

The movement of the shaft does the diverting, and the ms obviously then switches the boiler on. You could alter the ms temporarily and see if the rad pipes get hot when you turn the tap on. If so then the diverting isn't happening properly so you probably need a new diaphragm which is in there. But at least you'll have some HW until you can get to do it.

 

[Shamus]

thanks for the info ChrisR I've adjusted the switch and all seems ok. You seemed knowledgable on the Boiler I have i don't suppose you would know why my heating is making a whining/whiring noise after about 5 mins of being switched on. It seems to becoming from the upper half somewhere at the back of the boiler.

cheers again
Shamus

 

[kevplumb]

if the water isnt hard in the north of england why does hartlepool have the second hardest water in the country
by your description you mean the servo valve above the water section
classic sign of scaling is when it fails to open the diverter valve
which is on the bottom right of the boiler

 

[Shamus]

Not sure about the water in hartlepool but i am sure about the flow switch being on the left hand side of the boiler which then leads me to think i am not sure if it is a VCW and or a Sine. My manual is for both.

Re Quote - "The water is not hard in Carlisle"

 

[Shamus]

My Mistake

you mean the servo is on the left but the diverter is on the bottom right