How long do I drain back boiler for? Help and information on all topics relating to your central heating, air conditioning and ventilation issues.

[Steve1962]

Hi newbie on here, need some advice please, I'm wanting to replace my fortic cylinder which is heated via back boiler coal fire and immersion heater, how long do I drain back boiler before the cylinder heating coil empties so I can take Flow and return pipes off and drain the cylinder, TIA

[stoneyboy]

Hi steve1962,
We can’t tell you - drain the system until you think the coil will be empty, tentatively undo the bottom coil joint and if water comes out you have not drained enough out of the system.
Regards S

[Steve1962]

Hi thank you for that I'll do that and see, much appreciated for you reply