Hi gents, seems there is a lot of knowledge on this site so thought I'd try picking your brains.
We have had seemingly erratic HW and CH when required by tank/ room thermostats from our gas fired Potterton boiler for about a year. This is a pressurised system and the boiler is about 9 years old, was put in by a building contractor when the house was extended and extra rads added, etc. Originally suspected the zone valve, head has been replaced (last winter) and problems seemed to reduce for a while, but now it seems that the boiler will only fire for a short time and then the water supply from the boiler to the DHW/ CH goes cool. (It takes a bit longer to happen if only CH on but happens with any combination of DHW and/ or CH.)
Replaced a non functioning rad during the summer, it had sludge in it, did a partial flush of the system then (just from the fill to the open connection where the rad was removed) and got some black stuff out, considering a power-flush but wondering if the problem could be scale and hence this would be ineffective/ waste of money?
We live in a hard water area, the system appears to have been treated when new for corrosion but maybe not scale.
Coud this be a scale build up problem? (Has it been long enough?)
How can it be treated?
Is it worth doing a power flush (or maybe a mains water flush which I could probably manage myself?)
We have had seemingly erratic HW and CH when required by tank/ room thermostats from our gas fired Potterton boiler for about a year. This is a pressurised system and the boiler is about 9 years old, was put in by a building contractor when the house was extended and extra rads added, etc. Originally suspected the zone valve, head has been replaced (last winter) and problems seemed to reduce for a while, but now it seems that the boiler will only fire for a short time and then the water supply from the boiler to the DHW/ CH goes cool. (It takes a bit longer to happen if only CH on but happens with any combination of DHW and/ or CH.)
Replaced a non functioning rad during the summer, it had sludge in it, did a partial flush of the system then (just from the fill to the open connection where the rad was removed) and got some black stuff out, considering a power-flush but wondering if the problem could be scale and hence this would be ineffective/ waste of money?
We live in a hard water area, the system appears to have been treated when new for corrosion but maybe not scale.
Coud this be a scale build up problem? (Has it been long enough?)
How can it be treated?
Is it worth doing a power flush (or maybe a mains water flush which I could probably manage myself?)