no heating or hot water vaillant

20 Oct 2009
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United Kingdom
Hi all i have got a problem with a vaillant vc gb 242 eh boiler. The boiler lost pressure but since repressurizing the system there is no water running out of the hot water taps and the central heating isnt working either Please help, i would apreciate any ideas thanks :cry:
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If there's no water running out of the hot taps then you have turned off a valve that should have been left on. :confused:
hi thanks for the reply, i am asking these questions on behalf of a family member not sure if they have been messing with the boiler. Which valves could have been turned off that would cause this fault?
Either the cold in isolating valve or another valve in the supply line to the boiler.

Quite clearly whoever has touched it knew nothing about what he was doing.

The obvious answer is to call a heating engineer to service the boiler and bring it back to the correct operational settings.

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Quite clearly whoever has touched it knew nothing about what he was doing.

Elementry my Dear Watson. If the OP knew his
boiler, he would not be here asking questions. :LOL:
Hi i have checked the cold in isolating valve myself and it is ok, i know this because i drained the system down my self to make sure it wasnt air locked the system now has a pressure of just above 1 bar.
do you hear the pump running?

Citreon DS was a car ahead of its times. Hydraulics played a major part in keeping it on the road as it controlled steering, suspension etc.

Similarly, the pump generates pressures that are then used to control boiler functions.
And you dont see any DS left any more.

But there still a few of the earlier L15 left!
pump seems to run when i manually push the sero valve against the microswitch which then fires the boiler and the central heating works if i hold the switch closed but when i release it the system shuts down? but still no flow of water at hot water taps?
Sorry OP, the pump runs before anything else happens. It then powers the various parts in the boiler.

Take the pressure up to 2.5, then open the pressure relief valve to discharge the water to arount 0.5. Pressure relief valve may start passing, but your boiler may also work. You have an air lock in the system me thinks.
ok thanks is the bleeding procedure simple enough? have bled the radiators do i have to bleed the boiler itself?

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