Bleeding hot water system

[Brenjoe]

Hi, i have an oil boiler heating 3 zones, one of which is hot water. I removed a radiator last week so accordingly opened all 3 valves manually and drained the system before plumbing. On completion i refilled the system and vented the radiators from the bottom up. Both heating zones are operating perfectly, however my hot water zone is not. For that zones, the boiler is failing to start. If i have an airlock, how to vent the hot water zones, as i have done for the radiator zones?? Thanks in advance

 

[rogerp]

Hi Brenjoe,
I take it that you have an unvented system? Look in the cylinder cupboard and see if there is a manual screw type vent at the high point of the hot water coil, if so vent this and all should be good. If not I would lock open the zone valve to the hot water leaving the heating off. Generally there is little resistance to the coil on the cylinder pushing through an airlock on hot water only but if this doesn't suffice please let me know and I can go through several further ways in which to resolve this for you. regards Rogerp

 

[Brenjoe]

thank you