Vaillant VCW-sine 18 T3WF H
- Thread starter Jmolden
- Start date
have you bled the system
Can you hear the pump running?
did you open the aav ?
check system pressure ?
check system pressure ?
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Could be air in the domestic heat exchanger,slacken the slotted brass nut in the top of it to remove air.Theres also a manual bleed in the top of the main heat exchanger,but would need a registered engineer to access this.
Here's another did you; did you use a lot of flux or paste when fixing the leak, that can block some of the pipework within the boiler and as it forms part of the gas chain (remotely) you might want to get an engineer in to check it.
PS the air vent is manual but in the combustion area and you shouldn't go in there without gas competency.
PS the air vent is manual but in the combustion area and you shouldn't go in there without gas competency.
There is an auto vent on top of pump but as the last of this model was made in 1988 it prob won't work the best place to vent is as per earlier post the 17mm nut on top of dhw ht exch
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