Problem with pressure drop on an icon23T boiler

[SleepySmurf]

Hi everyone,

I've got a icon23T boiler that seems to be loosing pressure every couple of days (this has been going on for about a week now).

I've had this problem before and found a leak in the central heating circuit, which was repaired. The system worked great for about 3months and now I have the same pressure problem only slightly different.

The only thing that i have noticed that is slightly different in the symptoms of the boiler, is that the pressure gauge does not drop to zero like the last time, but it drops to about a quarter bar - enough for the boiler to stop firing up and heating water.

Could the drop in pressure be down to any other reason than a hole in the central heating circuit, ie. a faulty heating system safety valve (3bar) / expansion vessel or drain valve (i don't see any water coming out of the outside over pressure pipe)

Could anyone tell me whether the pressure should always eventually fall to zero, if i had a leak in the central heating circuit pipes or not.

I basically want to either eliminate or pinpoint if the boiler problem is due to a leak in the central heating circuit.

thank you very much for any help.

 

[breezer]

i am not a plumber or heating engineer, but as its a sealed sytem, it should never drop, because it has no where to go.

i have had a few probs with my boiler but all sorted, but a while ago, we were loosing pressure, slowly but still loosing it, yurned out that where i drained the system i had not done the drain valve 100% only a drip about once an hour but it was enough to drop pressure over a few weeks, so i am saying have you checked where the fault was last time, and any joints / "taps"