Glow-worm Flexicom 18sx boiler. The condensate trap only drips out water, not in designed slugs. I have researched the theory, and tested the trap both ins-situ and out of the boiler, and cannot understand why it doesn't work properly. As I understand it, the condensate water should rise in the tank until it overflows the annular gap; this provokes spillage which initiates siphonic drainage of the tank; the float falls, it seals the hole at the bottom and interrupts the flow, so the water seal remains intact.
Removing the trap and testing at the sink-side: filling the trap fails to provoke any siphonage. The only way I can force this is to insert an additonal lining tube to allow the water to rise higher than intended - and then it only releases a few mls, it doesn't drain the trap. I have obtained a second trap, and testing this also fails to siphon out.
I have cleaned and blown through the channels with compressed air. I have tested the condensate drain pipe, which is freely patent to drainage. The float has no leaks, and is not inverted. The plastic moulding shows no leakage, and the rubber seal is good. I cannot of course actually see inside the channels, but have no reason to suggest they might be blocked.
Even after videoing the boiler for hours, I have never seen the water level in the trap less that nearly full. I suspect it IS draining - but only a few mls at time, so is at risk of freezing.
What am I failing to understand? - or are both traps faulty (very unlikely). It is keeping me awake at night . . .
Philip
Removing the trap and testing at the sink-side: filling the trap fails to provoke any siphonage. The only way I can force this is to insert an additonal lining tube to allow the water to rise higher than intended - and then it only releases a few mls, it doesn't drain the trap. I have obtained a second trap, and testing this also fails to siphon out.
I have cleaned and blown through the channels with compressed air. I have tested the condensate drain pipe, which is freely patent to drainage. The float has no leaks, and is not inverted. The plastic moulding shows no leakage, and the rubber seal is good. I cannot of course actually see inside the channels, but have no reason to suggest they might be blocked.
Even after videoing the boiler for hours, I have never seen the water level in the trap less that nearly full. I suspect it IS draining - but only a few mls at time, so is at risk of freezing.
What am I failing to understand? - or are both traps faulty (very unlikely). It is keeping me awake at night . . .
Philip
