Ok, I have been around the house and balanced the rads with an IR
thermometer so that there is roughly a 12C drop across each. However,
once approximately every 24-36 hours the boiler and pipes around the
house start make a horrendous banging noise, forcing me to turn off the
heating for a period. I have read in a separate post this could be do
to do with reduced flow rate to the boiler - but why would it only bang
intermittently? Could it be an airlock instead? The banging does seem
to coincide with my balancing though. Any help greatly appreciated.

"newbie" wrote in message
ups.com...
Ok, I have been around the house and balanced the rads with an IR
thermometer so that there is roughly a 12C drop across each. However,
once approximately every 24-36 hours the boiler and pipes around the
house start make a horrendous banging noise, forcing me to turn off the
heating for a period. I have read in a separate post this could be do
to do with reduced flow rate to the boiler - but why would it only bang
intermittently? Could it be an airlock instead? The banging does seem
to coincide with my balancing though. Any help greatly appreciated.


Have you got TRVs on all rads? If so, they may be closing off, and with no
by-pass, will bang-a-go-go.

Angus

an easy way to try is to remove the thermostat head from any one of the rad valves. that way the rad will not close down and give you a bypass. if the noise stops that proves the problem. auto bypass valves should be fitted to all new installations see honeywell controls web site they sell one.
gaz.

No TRV's guys just standard LSVs and control valves. I've opened up
all the LSV's to increase flow rate, no banging so far, but lots of
gurgling around the system - does add weight to air in system
hypothesis?