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boilerjoe
I mainly do oil boilers and small plumbing jobs, so here goes. Need some help with a domestic central heating system. Its a two storey house with open vented F&E tank in the attic, copper cylinder in hotpress upstairs. Oil boiler supplying 19 rads with DHW and or CH switched from the timer, one motorised valve takes care of this, thermostatic valves, no room stats. Circulating pump is on the flow pipe from the boiler. Boiler is out in the garage and pipes run 10 metres before they enter the house.
Complaint was that the DHW temperature was not high enough and they would have the boiler on far too long to provide enough for showers and baths. Had a look round, no stat on the cylinder, just the boiler stat. The flow and return from the boiler come into the house and tee off, 22mm to CH and 15mm to coil. The motorised valve was on the CH pipe, just open or closed depending on DHW only or both. No zone control. Decided to go for a flush out of the coil and drained down the system. While in the attic turning off the feed supply I noticed the expansion tank was 'red with rust'. Anyway, drained the system and connected the garden house direct to the supply of the coil and ran water through this for a while. Reconnected coil and refilled the system with cleanser. Bled everything cold and cranked up the boiler. Reports from the lady of house were good, DHW was piping and that there was plenty of hot water for everybody. Not good was the constant need to bleed radiators. I put this down to the cleanser removing contamination and air developing from this?
Back one week later to dump the cleanser. Up at the tank and with the heat on prior to draining and was sure that I could see traces of flow back up through the supply pipe at the bottom of the tank. Only noticed this as the water was misty but definitely could see the traces of back flow.
Could this happen? If water is back streaming up the supply line is it sucking air through the vent? Could somebody advise please?
Drained the cleanser, refilled with anti rust and bled cold, all air out and radiators rebalanced, house is roasting. Been chatting to them everyday since and always needing to bleed upstairs rads.
Any advice would be gratefully accepted. My background is oil boiler service, part-time but I feel I have good understanding of all things mechanical/electrical. This house belongs to a cousin and lives a stones throw from me, I am dying to fix this for the good pr factor within the extended family.
Was reading the fernox site about 'pumping over' and 'see-sawing'.
I hope I have provided enough info, but if any more detailed stuff is required please ask me.
Thanks in advance
Joe
Complaint was that the DHW temperature was not high enough and they would have the boiler on far too long to provide enough for showers and baths. Had a look round, no stat on the cylinder, just the boiler stat. The flow and return from the boiler come into the house and tee off, 22mm to CH and 15mm to coil. The motorised valve was on the CH pipe, just open or closed depending on DHW only or both. No zone control. Decided to go for a flush out of the coil and drained down the system. While in the attic turning off the feed supply I noticed the expansion tank was 'red with rust'. Anyway, drained the system and connected the garden house direct to the supply of the coil and ran water through this for a while. Reconnected coil and refilled the system with cleanser. Bled everything cold and cranked up the boiler. Reports from the lady of house were good, DHW was piping and that there was plenty of hot water for everybody. Not good was the constant need to bleed radiators. I put this down to the cleanser removing contamination and air developing from this?
Back one week later to dump the cleanser. Up at the tank and with the heat on prior to draining and was sure that I could see traces of flow back up through the supply pipe at the bottom of the tank. Only noticed this as the water was misty but definitely could see the traces of back flow.
Could this happen? If water is back streaming up the supply line is it sucking air through the vent? Could somebody advise please?
Drained the cleanser, refilled with anti rust and bled cold, all air out and radiators rebalanced, house is roasting. Been chatting to them everyday since and always needing to bleed upstairs rads.
Any advice would be gratefully accepted. My background is oil boiler service, part-time but I feel I have good understanding of all things mechanical/electrical. This house belongs to a cousin and lives a stones throw from me, I am dying to fix this for the good pr factor within the extended family.
Was reading the fernox site about 'pumping over' and 'see-sawing'.
I hope I have provided enough info, but if any more detailed stuff is required please ask me.
Thanks in advance
Joe
