My central heating system was upgraded five years ago and has worked fine since then. It still works okay but I encountered a problem today when I replaced a radiator.
I have a sealed system (not a combi) working off a Keston Celsius 25 system boiler with separate pressure vessel , 2 zone valves and an old indirect hot water cylinder (no foam lagging)fed by a cold water storage cistern. There is no feed and expansion cistern-this was removed when the system was upgraded.The house is fairly small,only has two storeys and there are 8 radiators in total.
Anyway, I have replaced most of the radiators in the house in the last few years -I put a new drain off in under the ground floor at the system's lowest point and draining down used to take half an hour at the most before it stopped running.
Today I drained down to replace a downstairs radiator and the system was still draining with a vigorous dribble after THREE hours and showed no signs of letting up. After the first hour and thinking the filling loop might be open I checked this-it wasn't- but I disconnected it anyway-but it kept on draining.
I've filled the system back up and had it running again no problem.
I can't think of any other explanation than that the cylinder coil has a hole in it and is passing water into the heating system pipework. But how common is this?Even with an old cylinder like mine?
There is no evidence of this at the hot taps though and they are passing clear water-though the central heating water was pretty clean to start with so it might be hard to tell. I suppose it might have helped if I'd shut off the stop valve to the cold water cistern to see if it stopped running -but how long would it have taken to drain off 200+litres of stored water?
Can anyone offer any other suggestions what might be the cause?
Thanks for looking.
I have a sealed system (not a combi) working off a Keston Celsius 25 system boiler with separate pressure vessel , 2 zone valves and an old indirect hot water cylinder (no foam lagging)fed by a cold water storage cistern. There is no feed and expansion cistern-this was removed when the system was upgraded.The house is fairly small,only has two storeys and there are 8 radiators in total.
Anyway, I have replaced most of the radiators in the house in the last few years -I put a new drain off in under the ground floor at the system's lowest point and draining down used to take half an hour at the most before it stopped running.
Today I drained down to replace a downstairs radiator and the system was still draining with a vigorous dribble after THREE hours and showed no signs of letting up. After the first hour and thinking the filling loop might be open I checked this-it wasn't- but I disconnected it anyway-but it kept on draining.
I've filled the system back up and had it running again no problem.
I can't think of any other explanation than that the cylinder coil has a hole in it and is passing water into the heating system pipework. But how common is this?Even with an old cylinder like mine?
There is no evidence of this at the hot taps though and they are passing clear water-though the central heating water was pretty clean to start with so it might be hard to tell. I suppose it might have helped if I'd shut off the stop valve to the cold water cistern to see if it stopped running -but how long would it have taken to drain off 200+litres of stored water?
Can anyone offer any other suggestions what might be the cause?
Thanks for looking.
