Jaguar 23k F0 error and possible fault PRV

16 Jan 2010
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United Kingdom

hope you guys can help, i have a jaguar/protherm 23k combi. recently there has been alot of water coming from overflow outlet on my boiler, and every know and again its been constantly running like a tap. then it stopped, its happened again today, so decided to check it out. Boiler was at 4.4 pressure when cold, so it was just the prv doing its job.The pressure i think was caused by the top up pipe being left slightly open (forgive my mind has gone blank silver tube that tops the boiler up) so i closed this fully and the pressure when back to normal.

However this morning, i woke up to F0 error, which manual says
loss of water
air lock on boiler
pressure sensor failure

So i opened the top up valve and corrected boiler back up to correct presure.

how the boiler seems to work fine, but i suspect it may be a faulty prv valve which isnt shutting 100% and there for would this be the cause of the loss of water?

thanks in advance for your help!
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It all seems very simple.

You left the filling valve open, did not remove filling loop as required by the building regulations, and the PRV opened to relieve the excess pressure.

If that was for long you may have created sludge in the system from the new oxygen rusting the inside of the rads.

The PRV may be retrievable by clicking it a few times or if not may have to be replaced. See FAQ for more info.

thanks for the advice, but like to state, that the boiler is serviced every year via british gas and the filling loop has been there since we moved in. If this should have been removed, then why havent british gas mentioned it and removed it?

as i am not an expert on these things i just assumed it was meant to be there! why does it have to be removed?


whaat happened to the prv when the top is clicked? thanks
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Loop should be removed to comply with Water Regs and this stops leaking into the boiler as yours did.

Ask BG anything about what they did or did not tell you.

See FAQ for details of clicking a PRV.


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