I am hoping that someone can give me some advice in order to solve my CH problem. I have searched these forums for tips and hints but am still at a loss.
The System
Boiler is a Potterton Suprima 70L and is approx 6 years old. It is situated downstairs in our utility room.
The Pump is situated upstairs in our airing cupboard, together with the Hot Water cylinder. Recently our pump had become quite noisy. The pump is at least 16 years old. (It was there when we moved in).
A header tank is situated in the loft. Which is filling up without any problems
I noticed that the downstairs radiators weren't getting very hot, while the upstairs ones were, so drained down the system (A lot of black sludge and metal filings? came out). I let the system flush through for some time before refilling.
I then re-filled the system and vented the radiators, left it for 30 mins to settle and then started the heating.
This is where the problems start.
On restarting the heating I discovered, that:
The Boiler fires up for approximately 60 seconds then a lot of banging is heard and hissing and what sounds like water/air rushing through the two pipes going into the boiler. The Boiler then switches off, the red light flashes the green light remains on. The two pipes into/out of the boiler are very hot.
At no time does the heating itself get hot.
I have so far:
Removed bleed screw from pump and inserted a small flatblade screwdriver and can confirm pump is working. However, if I leave the screw off, the pressure produced is not that high, (however I do not really know what flow it should produce).
Drained the system down again and flushed it through from the header/expansion tank, until the water flowed clear.
When I drained the system down, the pipes into out of the boiler remained hot, even though the system was drained down, is that due to a non return valve?
Then I added Fernox Central Heating restorer to the header (While system only half full), then let it top back up and vented the rads etc. This has been in the system now for about 3 hours but as yet has made no difference?
My thoughts are either a blockage between Boiler and pump or a faulty pump.
Any hints, advice or help very much appreciated, Merry Christmas
The System
Boiler is a Potterton Suprima 70L and is approx 6 years old. It is situated downstairs in our utility room.
The Pump is situated upstairs in our airing cupboard, together with the Hot Water cylinder. Recently our pump had become quite noisy. The pump is at least 16 years old. (It was there when we moved in).
A header tank is situated in the loft. Which is filling up without any problems
I noticed that the downstairs radiators weren't getting very hot, while the upstairs ones were, so drained down the system (A lot of black sludge and metal filings? came out). I let the system flush through for some time before refilling.
I then re-filled the system and vented the radiators, left it for 30 mins to settle and then started the heating.
This is where the problems start.
On restarting the heating I discovered, that:
The Boiler fires up for approximately 60 seconds then a lot of banging is heard and hissing and what sounds like water/air rushing through the two pipes going into the boiler. The Boiler then switches off, the red light flashes the green light remains on. The two pipes into/out of the boiler are very hot.
At no time does the heating itself get hot.
I have so far:
Removed bleed screw from pump and inserted a small flatblade screwdriver and can confirm pump is working. However, if I leave the screw off, the pressure produced is not that high, (however I do not really know what flow it should produce).
Drained the system down again and flushed it through from the header/expansion tank, until the water flowed clear.
When I drained the system down, the pipes into out of the boiler remained hot, even though the system was drained down, is that due to a non return valve?
Then I added Fernox Central Heating restorer to the header (While system only half full), then let it top back up and vented the rads etc. This has been in the system now for about 3 hours but as yet has made no difference?
My thoughts are either a blockage between Boiler and pump or a faulty pump.
Any hints, advice or help very much appreciated, Merry Christmas
