vaillant combi compact vcw gb 242 eh water valve

[zenith]

please help.
i have a hot water issue with a vaillant combi compact vcw 242 eh its luke warm so i have bought a new valve part number 011299 and it looks the same but my old one has a small copper pipe about 4mm thick that goes to a small vessel inside the boiler off the top of the water valve and the new one hasn't got the connection on it for the copper pipe, in the new valve kit there is a small metal like tube with a nut on it, can any one tell me if this is to blank off the vessel and how,,,,, i know they got rid of the vessel in the later models and on the internet they say this valve superseeds older valves

kind regards
shaun

 

[Gasguru]

What makes you think the water section's faulty...if the boiler's firing up on a hot water demand it's probably some other issue.

 

[Wongfeifox]

Is this small vessel you talk of about the size of a tennis ball and blue ? This may be the mains mini expansion vessel and depending on mains water pressure, may, or may not be required. Please do not turn down the stop cock, this adjusts flow, not pressure.
I can't recall, but is the 242 eh like the sine 18 where the water section actually lifts the gas valve, if so it could be the diaphragm not lifting high enough or a restricted Venturi in the water section, if the gas section is separate from the water section (ie not directly above it) then as said before it could be that it has nothing to do with the water section. Are you getting the correct burner pressure when it fires for hot water, is it passing down the heating flow, does it modulate down within a few seconds of firing up ?

Need more input, input.. INPUT...

 

[zenith]

thanks guys
the burner pressure is the same on the hot water as it is on the heating it doesn't increase when hot water demand is on

the hot water temp dial on the front underneath the panel has seized up and wont turn so i have taken it out and its all broken and came out in bits, my original plan was to just swap it for the new one that came with the new valve but its slightly changed and wont fit thats why i wanted to change the whole valve but because of this new valve not having the out let on it for the small copper tube i cant, apart from that the valve is exactly the same and i wanted to know if this will work and what is the small metal tube with a nut on for is it for blanking off the small vessel in some way

kind regards
shaun.

 

[Gasguru]

A second or two after the burner fires up the green led just to the right of the on/off switch should light up....at that moment the burner flames should be seen to increase in height...does this happen?

 

[Bunnyman]

Fit the valve, leave the blanking screw in it. Don't connect the small copper pipe just bend it out the way.. As said its unlikely the valves the fault anyway.

 

[zenith]

Fit the valve, leave the blanking screw in it. Don't connect the small copper pipe just bend it out the way.. As said its unlikely the valves the fault anyway.

the issue i have is there doesn't seem to be anywhere to put the blanking plug or if it is a blanking plug at all, never fixed a vaillant this old before we usually replace boilers that are this old but this guy is a mate thats skint so helping him out

 

[zenith]

A second or two after the burner fires up the green led just to the right of the on/off switch should light up....at that moment the burner flames should be seen to increase in height...does this happen?

im going back there tomorrow so i will check, never worked on a old boiler of this age before we usually replace them with new ones

 

[Bunnyman]

Just fit the valve mate an ignore the pipe. U will c there is a screw headed plug where the pipe used to go on the new valve but thats redundant now

 

[zenith]

Just fit the valve mate an ignore the pipe. U will c there is a screw headed plug where the pipe used to go on the new valve but thats redundant now

i will do it tomorrow
just wasn't sure and didn't want to strip the boiler down and find it wasn't compatible and leave him with no heating as-well as no hot water....
not a job to be tackled at 1pm on a Saturday afternoon when every merchant is closed

 

[Gasguru]

I don't know why you're fitting the water section.....it's unlikely to be the problem and if you want to preserve the friendship fitting unecessary parts is not a good idea