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Mend Vaillant VCW 303/3-3 Combi Boiler No Hot Water

no hot water, combi boiler, vaillant vcw sine t3w?

not getting hot water when turning the tap on, sometimes the tap has to be turned on full then the combi boiler clicks and in a few minutes the hot water is on, other times it does not work at all so I get cold water. The heating system is ok.

raj mistry
January 2007
Microswitch just done one

becks
October 2009
I think the problem could be with the small differential pressure valve at the front of the boiler above the solenoid. Remove it gently be unscrewing its three holding screws and pull it forward with the small bore water pipes still in place. When you turn on the hot water the valve should operate smoothly.
This can be observed by watching the plunger. It should return when water goes off. approx 27 quid.

Keith
March 2008
More than likely to be the diaphram in the H/W housing in the boiler.
Please use C.O.R.G.I registered engineers for this kind of work on gas appliances.
A vintage boiler like the sine can take your head clen off, if not treated with respect.
Hope this helps.

Christian.
January 2007
poss dhw flow sensor

hi-spec plumbing
January 2007

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