Gemini 960e combi boiler problem Help and information on all topics relating to your central heating, air conditioning and ventilation issues.

[sailoncj]

Hi,
When HW tap was turned on last night there was loud gurgling in an adjacent radiator.
Check of CH system pressure guage on boiler showed that it had fallen significantly and when re-charged from mains water quickly falls back again when HW is drawn.
HW and CH seem to be otherwise operating ok.
Am I right in thinking the problem is a heat exchanger failure or could there be other causes?
Also, am I right in assuming the HW could be contaminated?
I would be grateful for any assistance on this
M/thanks
sailoncj

[eggers]

could be a blockage in the dhw plate heat exchanger or in the manifolds, when the pump runs on the hot water circuit, with nowhere for the water to go, the pressure could built up and dump out of the pressure relief valve.
Unlikely the hw will be contaminated as the mains pressure water is higher then the central heating pressure, so what will happen in that scenario is the central heating pressure will continually rise and constantly vent out of the pressure relief.

[sailoncj]

M/thanks for your help Eggers and apologies for not getting back sooner:
In the event the problem was very low tech - Found water was leaking from around the large collar nut that attaches the 3-Way to the Htg manifold - Can only assume that it was never tightened properly and had been weeping for some time, gradually worsening as the fibre washer disintegrated. Anyway, all sorted now!
Thanks again!