On Thu, 20 Apr 2006 02:28:32 -0700, Martin Pentreath wrote:

Thanks for all advice. I have now found and studied the water circuit
digram and am a little wiser about how combis heat the domestic hot
water. However, this boiler seems very annoying - I can isolate the
primary circuit easily at the point where the CH flow and return enter
the boiler, but I can't then find any way of draining the water from
within the boiler. I'm just going to have to drain the whole system
down and replace the inhibitor.

I've looked through the manual and it seems, sadly, you are right.
However you may find that you can release the pressure with a drain cock.
Then isolate and then remove the water from the boiler by opening a a
union (you won't get sprayed if you have released the pressure).

If the boiler is above the rads you have a much better than even chance of
keeping the water in the rads.

IMHO it is exactly this sort of feature (or lack of it) that is the
difference between the differing quality of boiler models.


--
Ed Sirett - Property maintainer and registered gas fitter.
The FAQ for uk.diy is at http://www.diyfaq.org.uk
Gas fitting FAQ http://www.makewrite.demon.co.uk/GasFitting.html
Sealed CH FAQ http://www.makewrite.demon.co.uk/SealedCH.html
Choosing a Boiler FAQ http://www.makewrite.demon.co.uk/BoilerChoice.html