Vaillant VCW 18 Sine Combi Bolier, stopped firing up.

[lemonphonedart]

Hi all, I have a Vaillant VCW 18 sine Combi Boiler that has been discussed quite a few times on this site.
Back in march it stopped working and i came onto this site and two very helpfull gents helped me find the re-set button. After pushing this all was fine until now (two days before christmas) the re-set is not working either now, the pilot light is on, but the boiler just wont fire up.

Does anyone have any idea's? any heating engineer i call just wants to sell me a new boiler, and i wouldn't mind but they said that last time and i fixed it myself with the help from this site.

 

[Bunnyman]

Press the red button til pilot goes out then leave it for 5 mins til u hear a click ,hopefully it will reset then go through the pilot lighting procedure that's n the inside of the door

Untitled

• Bunnyman
• 26 Mar 2010
• 499

 

[The831Bunny]

Hi

First things first, Is the boiler making any noise? Has the electric been turned off to the boiler.

The pump may have jammed. Feel the pump and see if it's hot. You can remove the large chrome screw in the centre and have access to the end of the pump shaft. Use a thin electrical screwdriver to engage in the small slot on the shaft end. See if it's free to turn. Place an old towel under the pump to catch any dribbles. You may find you can ease the shaft back and forth to unstick it (oo er Missus!).

Also you can try pressing the red push button, waiting three minutes, then relighting the pilot as per the instructions on the door. Sometimes the buttons can get knocked and the power to the pump is cut but the pilot remains on. Doing the above sorts that.

 

[The831Bunny]

Press the red button til pilot goes out then leave it for 5 mins til u hear a click ,hopefully it will reset then go through the pilot lighting procedure that's n the inside of the door

Untitled

• Bunnyman
• 26 Mar 2010
• 499

Bugger; beaten to it lol!

At least we are consistent mate

 

[lemonphonedart]

Hi mate, thanks for the reply, I have turned off till the click then re-lit pilot, still no joy I'm afraid.

 

[Bunnyman]

Try the overheat reset again and then follow 831 s excellent instructions!

Untitled

• Bunnyman
• 26 Mar 2010
• 499

 

[lemonphonedart]

I fellas, the pump is cold, as is the whole boiler, I have reset it twice, and used overheat button, nothing seems to be working.
The electric has not been cut.

 

[Bunnyman]

Is the red neon lit,? Can u check with a meter if u have power to 1 an 2 terminals at boiler?

 

[The831Bunny]

Make sure your controls are on for heating. Have you tried the hot water?

Can you hear any click from the boiler when you first turn on the mains?

 

[lemonphonedart]

The red neon is lit so it has power, there is no click if turn the red button off and on again.

 

[The831Bunny]

If u r confident with electrics test for 240v live (phase) at terminal 3 on the terminal strip. That's inside the rectangle box on the rhs of the large aluminium control box with the push button on. You can use a neon screwdriver, but testers are better.

 

[lemonphonedart]

I'm not THAT confident with electrics, I do have a friend who is an electrician, but doubt I could do anything till after Christmas.
Thanks for the advice, just wish there were heating engineers round here who were so knowledgable or at least willing to try and fix it. Rather than 'you need a new one, I do very competitive rates'.

 

[Agile]

Does anyone have any idea's? any heating engineer i call just wants to sell me a new boiler, and i wouldn't mind but they said that last time and i fixed it myself with the help from this site.

Another poster who says no body will come and fix it for him!

OP, are you able to measure to see if power is being applied to the pump?

Can you operate each rocker switch about 12 times? Sometimes the3 contacts get oxidised.

Tony

 

[The831Bunny]

Does anyone have any idea's? any heating engineer i call just wants to sell me a new boiler, and i wouldn't mind but they said that last time and i fixed it myself with the help from this site.

Another poster who says no body will come and fix it for him!

OP, are you able to measure to see if power is being applied to the pump?

Can you operate each rocker switch about 12 times? Sometimes the3 contacts get oxidised.

Tony

Theres no click from the DC solenoid Tony which occurs when everything is OK but the pump is stuck. The OP says no click so it sounds like the electronic pcb or fuse fuse has gone and the pump is in position II, or theres a problem with the mechanism in the push button switch box. Can't say with most of my senses removed! Its amazing how difficult it is to fault find with one sense removed, let alone all of them!

 

[lemonphonedart]

Hi Fella's, after another cold night and going to mother in laws for shower I have still had no joy.
I have however opened the rectangle box containing the main electrics and discovered its very wet inside so a leak must have caused the damage.

At total loss now, i don't have the expertise, and no experts will help apart from the new boiler thing, so looks like i will have to do that.

any recommendations for cheap-ish but quality boiler?