Wants help for Valliant Combi Boiler VCW 221H GC No.4704414

Sharks · 17 Nov 2009

Hi Guys,

I have very old but very relaibale vallaint combi boiler but unfortunetly I am having a problem with my faithful. I think I have identified what seems to be the problem, it seems that diverter valve is sticking and some time systems fires up and some time it just do not want to know.

I have been told to change the valve with new one but I am sure this day and age you can buy a service kit for it. Does any one know where would I find this as valiant and their stockist do not stock and they only want to sell me whole new Valve, which is madness to spend £90 quids or so.

If any one with any advise or idea whether I should attempt to change this my self or call a specialist.

Will appreciate any help.

Cheers
Sharks

mickyg · 17 Nov 2009

what vaillant boiler?

kevplumb · 18 Nov 2009

mickyg said:
what vaillant boiler?

221 mick

i would check the servo valve operation and water section first

Sharks · 18 Nov 2009

Servo is working fine no problem with hot water. But I have shower dismantled cos of refurbishment. Do you think because of this that I might have some air lock in the system as hot & cold water pipes are open and exposed.

Cheers
Sharks

kevplumb · 18 Nov 2009

you may be getting hot water but if the servo valve don't fully close the diverter won't change over

try pressing an the right of the cam and see in it moves down

namsag · 18 Nov 2009

As Kev say.
the fault finding leads to divertor but it is actually a worn servo not going all the way back (even a tiny bit makes all the difference) .
Or pin in water section scaled up and not fully returning holding servo partially open

Sharks · 18 Nov 2009

Yes Mick by pressing the cam on Diverter Valve it works fine and heating comes on. But when u switch the hot water back again heating goes off until u press the cam back again. So u recon Diverter valve at fault?

Cheers Sharks

kevplumb · 18 Nov 2009

namsag said:
As Kev say.
the fault finding leads to divertor but it is actually a worn servo not going all the way back (even a tiny bit makes all the difference) .
Or pin in water section scaled up and not fully returning holding servo partially open

servo valve or water section HONEST

darn sight cheaper to sort than a new diverter

DP · 18 Nov 2009

Shark, Kevin and Namsag have already (based on great experience) suggested you look at the servo NOT the diverter valve. Servicing the diverter valve will be good but fault is not in the diverter valve but servo is defective.

As the servo is NOT restoring fully, primary water that positions the diverter for heating is lacking in quantity to do the positioning, so no heating until your fingure does the trick.

When asking for hot water, water section spindle positions the servo cam (same as your fingure when restoring the cam to home position)

You are asking for advice then not taking it.

Sharks · 18 Nov 2009

Hi DP,
Ok man keep it cool I am taking advice but I know what is my boiler doing. I have looked at servo again and cleaned the spindle which shoots to get hot water cam activated. Still no response when it comes to firing the boiler.

I had to intervene with my finger again to Diverter Valve cam to close the micro switches and boom there she goes we get the heat.

I do respect the feed backs from you guys but in my opinion servo is functioning in it's place, or am I missing the point that the whole servo needs to be taken off and cleaned up.

Kev and Namsag welcome to comment please.

Cheers
Sharks

DP said:
Shark, Kevin and Namsag have already (based on great experience) suggested you look at the servo NOT the diverter valve. Servicing the diverter valve will be good but fault is not in the diverter valve but servo is defective.

As the servo is NOT restoring fully, primary water that positions the diverter for heating is lacking in quantity to do the positioning, so no heating until your fingure does the trick.

When asking for hot water, water section spindle positions the servo cam (same as your fingure when restoring the cam to home position)

You are asking for advice then not taking it.

kevplumb · 18 Nov 2009

I do respect the feed backs from you guys but in my opinion servo is functioning in it's place, or am I missing the point that the whole servo needs to be taken off and cleaned up.

if the servo valve is not returning fully even 1/16"" can make the difference

the diverter wont work

if you can push it down with your finger and the boiler starts

then there is your problem

the spindle on the water section is adjustable BTW it may have been altered

other than that

change the servo valve

word of warning DON'T mix the tubes in the front up

View media item 8355

Sharks · 18 Nov 2009

Hi Kev,

Thnaks for this pic yes I follow u but its not when I put finger on servo cam, its when I push the microswith carrier on diverter valve only then the boiler fires back again. I can aslo hear the whistling noise of boiler pressure. So dont know mate what's seems to be happening. I am confused.

Cheers
Sharks

kevplumb said:
I do respect the feed backs from you guys but in my opinion servo is functioning in it's place, or am I missing the point that the whole servo needs to be taken off and cleaned up.

Click to expand...

if the servo valve is not returning fully even 1/16"" can make the difference

the diverter wont work

if you can push it down with your finger and the boiler starts

then there is your problem

the spindle on the water section is adjustable BTW it may have been altered

other than that

change the servo valve

word of warning DON'T mix the tubes in the front up View media item 8355

kevplumb · 18 Nov 2009

if you press the switch regardless the boiler will fire

na tell yer what

forget what has been posted and go spend your hard earned and change the freakin diverter

then start a new thread as to why it didn't work

DP · 18 Nov 2009

What can anyone say. You know your boiler.

Sharks, can you write sequence of operation for this boiler i.e. clock makes a demand, something happens making something else operate to move thinmyjig etc.

Sharks · 18 Nov 2009

Hey Kev, I understood first time what you said but I just wanted to play devils advocate, but never mind I have come to conclusion that I will get the servo change after all and take it from there.

So Kev and DP and all of you who contributed to this wiki, all the best and kev mate keep it cool ok

Cheers
Sharks

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Wants help for Valliant Combi Boiler VCW 221H GC No.4704414

namsag

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