Some advice please;
I've a Potterton Promax Fsb boiler and an open vented system which is suffering from excessive gas in 2 towel radiators.
I've established that the system needs drained, flushed & refilled with inhibitor, as the Magnaclean filter was quite heavily contaminated with black gunge, and the water in the system is pretty black. It was drained and treated 2 years ago.
The 2 radiators in question need frequent bleeding, however all over radiators seem fine. Presumably as their neer the top of the system etc.
I've fitted auto-bleed valves, however, they dont seem to be working and the radiators still have gas trapped at the top. I'm assuming this is because the small hole in the auto bleed valves have possibly clogged up.
I've assumed the gas is from the corrosion products in the system and should get better when the system is flushed & re-treated.
So (and sorry for the long post) the CH pump makes a bit of a "whooshing" noise when it first starts up, which I assume is the gas in the system.
However, I'm wondering if the pump may be actually failing, and is drawing in air when it starts up. Theres no leaks visible.
I've also checked the pump isn't over pumping into the header tank, and I've also run it at different speeds.
Also the pump is noisier (I think) but may be imagining it.
Lastly (honest), the boiler very occasionally goes into overheat trip (red light flashing) and I usually need to waiting for 15 minutes or so until it will reset.
So, I'm wondering if all of these symptoms point to a knackered CH pump?
I'd welcome any advise of suggestions.
Thank you
I've a Potterton Promax Fsb boiler and an open vented system which is suffering from excessive gas in 2 towel radiators.
I've established that the system needs drained, flushed & refilled with inhibitor, as the Magnaclean filter was quite heavily contaminated with black gunge, and the water in the system is pretty black. It was drained and treated 2 years ago.
The 2 radiators in question need frequent bleeding, however all over radiators seem fine. Presumably as their neer the top of the system etc.
I've fitted auto-bleed valves, however, they dont seem to be working and the radiators still have gas trapped at the top. I'm assuming this is because the small hole in the auto bleed valves have possibly clogged up.
I've assumed the gas is from the corrosion products in the system and should get better when the system is flushed & re-treated.
So (and sorry for the long post) the CH pump makes a bit of a "whooshing" noise when it first starts up, which I assume is the gas in the system.
However, I'm wondering if the pump may be actually failing, and is drawing in air when it starts up. Theres no leaks visible.
I've also checked the pump isn't over pumping into the header tank, and I've also run it at different speeds.
Also the pump is noisier (I think) but may be imagining it.
Lastly (honest), the boiler very occasionally goes into overheat trip (red light flashing) and I usually need to waiting for 15 minutes or so until it will reset.
So, I'm wondering if all of these symptoms point to a knackered CH pump?
I'd welcome any advise of suggestions.
Thank you