Help why do things always break at xmas (Potential blockage)

[montechristo]

Guys,

a second opinion would be appreciated.

The System

3 years old
Fully pressurised
megaflow hot water cylinder
Gloworm 30sxi condensing boiler
each room indivually zoned with own thermostat

exception is main/onsuite bathroom which are on teh same stat and diverter valve

Recent work

British Gas have replaced the ignitor, internal condensor trap, and pressure releif valve to attempt to cure an F1-F4 error relating to ignition failure. (all done yesterday)

Touchwood so far seems to have cured that problem

Todays issue

a number of rads aren't getting very hot, biggest issue is onsuite bathroom which has been very hot since installed (3 weeks ago) which is stone cold.

The main bathroom rad is red hot and served by the same thermostat and diverter valve.

I've been in the loft and traced the pipe runs. Main bath rad pipe work is hot all the way from the valve to the rad, both flow and return

pipe work from diverter valve to onsuite rad is red hot for the first 0.5m then goes stone cold. All pipes flow and return from onsuite rad are stone cold. The pipe work goes from red hot to stone cold in the middle of one pipe run over say 1 inch length.

My guess is a sludge build up?

Would you concur?

thanks,

MArk.

 

[oilman]

Possible, but unlikely at 3 years old.

 

[montechristo]

so what else would cause a pipe to go from roasting hot to stone cold over teh course fo 1 inch of pipe?

 

[ChrisR]

An air lock.

 

[montechristo]

wll I'm guessing your right aboput the airlock

having spent all last night withthe boiler banging and poping like you wouldn't beleive the rads are now working again.

strange

 

[Paul Barker]

So how long did BG spend refilling system?

Now switch off boiler, bleed all rads, bleed pump, ensure auto air vent dust cap is undone one full turn, top up pressure. If still bangs a lot call their boss.