Draining a combi boiler

[Jupiter01]

I need to do some maintenance on a rad and wanted to check if the boiler can continue to run with 0 pressure on the boiler and whether this will affect hot water supply?

 

[Wayners]

No boiler won't run on 0.

My mates did though and it burnt out. Must have had a sensor fault.
Always switch off if you're draining.

Don't need to drain combi as it's s sealed system. Read up on that

 

[Jupiter01]

So if I am doing this work over a couple of days, I need to fill up the system again with rad pipes capped off as else there will be no hot water.

And then the following day I need to drain down again, put the rad in and fill up again. Have I got this right?

Thanks for your help.

 

[Wayners]

Yeah. Just put inhibitor in when you're on the final fill.
Oh. It's a sealed system so water can be slow coming out or even stop

 

[Madrab]

So if I am doing this work over a couple of days, I need to fill up the system again with rad pipes capped off as else there will be no hot water.

If you are just working on the rad on a sealed system then just turn off the rad valves, drain the rad, no need to drain the system and the system can stay running.

If doing work on the valves etc then the whole system wouldn't normally be drained just drained until depressurised and then the water should stop. If depressurising though then yes, boiler off until work is done