"Tim" wrote in message
m...
Chaps hi,

hoping for a bit of advice here. I have recently moved house to a
property which was built circa 1987. One item picked up on the survey
was that when the bolier came on (ch or hw) it made lots of loud
banging noises. So it has been doing this for at least 6 months

This didn't bother us too much but now we have started to use the CH
with the onset of winter it is waking us up every morning with a
*very* loud BANG. Having recently had the old analogue programmer
fail (and having to update it and the thermostat myself) I have
decided that it has to be worth an attempt at self diagnosis - and
then possibly trying to fix it myself or get some one in.

I have looked through similar posts but was hoping that this might
make sense to someone out there.


Two ideas spring to mind:

1. Air in the boiler- especially if the neither of the water pipes exits the
boiler at the top and continues 'up' . (If they don't, air can get trapped
in the boiler and it will stay there- in the extreme enough can collect to
stop the boiler lighting.) There is (usually) a bleed valve in the boiler
at the top of the heat exchanger.

2. Is the pump starting up reliably? If it 'sticks' the water in the heat
exchanger could be boiling, making the 'bangs' and the shock kicks the pump
to life.


--
73
Brian
G8OSN
www.g8osn.org.uk
www.amateurradiotraining.org.uk for FREE training material for the UK
Foundation and Intermediate Licences
www.phoenixradioclub.org.uk - a RADIO club specifically for those wishing
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