vaillant vcw sine 18

[desrob]

does anyone know how to take gas inlet pressure on this beast of a boiler and gas valve.there is a test nipple on the gas inlet pipework buts it's behind the boiler and impossible to get at..or is it..and i'm after the manual.

 

[Dotty]

Have a butcher's here

[DLMURL="http://www.gotogasdocs.co.uk/boiler-manuals/232-vaillant"]Vaillant Free Boiler Manuals Free Gas Manuals[/DLMURL]

 

[Leo21]

If you can't get to the nipple gas rate it.

 

[stevetheplumber]

from memory isnt there a test nipple just above the gas valve on the inlet to burner
left of dead center as you look at it or if its room sealed i think its on base of combustion chamber looking down again to the left of gasvalve you can do inlet working preasure from by the gas shut of valve on the jig

 

[Hobo128]

Just been to one of these today, I could manage to get to the inlet pressure, it is on the side of the gas valve right at the back, a pain to get to. Anyway i checked the burner pressure which should have been 10.6mb it was 12.5 and the combustion ratio was reading 0.0056. very high. Does anyone no how to adjust the burner pressure on these boilers???? I'm struggling

 

[Barry98]

Thread revived and moved to gsr

 

[stevetheplumber]

these old beasts were never made to be combustion tested ,is it this one with the little wire sealed door/flap on the front of the solenoid for adjustment im just getting the book but its a long download

 

[stevetheplumber]

pictures in the book ive found dont show it clear but im sure it was under a cap or flap that was wire sealed on right side above the solenoid its definately not the adjusting screw near the base of the solenoid thats a slow ignition device

 

[tamz]

Adjusting the inlet pressure isn't going to affect the readings.
It needs a strip down service.

 

[Hobo128]

I have stripped it down and cleaned, the burner pressure was up to 12.5mb should be 10mb according to mi. The ratio was about 0.0056. Some one said that after a service the ratios will be higher than normal for a while until it settles, how true is this. ??? I had to AR it anyway until I can work it out. Was hoping I could make some adjustments on it. Although its very old

 

[Hobo128]

Ok just to finish this thread off:

Went back to the boiler today. Check ratios. 0.0056 again. Well high. Burner pressure 14mb. Well high. Took boiler to pieces to out heat ex changer, straightened out all the fins, cleaned of all the calcium spots all over it, noticed a big split in the heat exchanger and a big hole on the back. Cleaned burner and put heat ex changer back. Adjusted burner pressure back to 10.6 mb as MI stated, (As someone said I think it was Ray, the burner pressure adjustment is under a sealed flap above the differential valve) and fired it up! Took my ratios again and it was 0.0008 - 0.0012.

Very happy with that! Anyway I ID it in the end because the case had a small split in it, I rang Gas safe technical and they said I was not being over cautious to ID it.

New boiler time. Thanks for the help...... Till next time

 

[Pssst]

Sine 18..a wonderful piece of kit....sigh...