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- 14 Feb 2010
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I installed a Worcester Bosch 18RI to an existing open vent system but there is really bad circulation. some rads ok to Luke warm and a couple still cold.
I have been back 3x to bleed air out of the system. 2 rads particularly bad. Air still rattling past pump (located in basement) and boiler. The flow is piping hot, but the return only slightly warm.
System: open vented s-plan, all ground floor, f&e tank quite high (approx 3m). The expansion pipe tees off the flow at the boiler. Can't see where feed, cylinder connections are. All rad valves crappy twin ended type. The customers say it worked fine before new boiler. I have also changed the pump. Was reasonably clean water when I drained it.
Old boiler was wall hung Netaheat cast iron. I have put in pump over-run and bypass (yes I have set this so it it not passing when it shouldn't).
I am therefore wondering:
- can there still be air in it after several bleeds.
- could the system be drawing in air? When I haven't changed the pipes.
- what else could it be?
Any advice and wisdom would be gratefully appreciated...thanks G
I have been back 3x to bleed air out of the system. 2 rads particularly bad. Air still rattling past pump (located in basement) and boiler. The flow is piping hot, but the return only slightly warm.
System: open vented s-plan, all ground floor, f&e tank quite high (approx 3m). The expansion pipe tees off the flow at the boiler. Can't see where feed, cylinder connections are. All rad valves crappy twin ended type. The customers say it worked fine before new boiler. I have also changed the pump. Was reasonably clean water when I drained it.
Old boiler was wall hung Netaheat cast iron. I have put in pump over-run and bypass (yes I have set this so it it not passing when it shouldn't).
I am therefore wondering:
- can there still be air in it after several bleeds.
- could the system be drawing in air? When I haven't changed the pipes.
- what else could it be?
Any advice and wisdom would be gratefully appreciated...thanks G