Advice on draining a boiler

[Stevecc]

Hello

I was wondering how to go about draining down a boiler in a two storey house (ground and first floor). The boiler is located in a bedroom on the first floor. 4 radiators first floor, 3 radiators ground floor.

Tubing to the ground floor radiators goes into the subfloor, in other words tubing goes below the ground floor level.

I understood that it was needed to drain a boiler from the lowest point. I can drain it from one of the radiators on the ground floor but this will leave water in the tubing in the subfloor.

Is that the normal way to do it, i.e. leave water in the subfloor tubing

 

[seco services]

What you draining it for ?
If working on rads not a problem

 

[Stevecc]

I have a problem with an expansion vessel. I have charged it and I am going to watch to see if system maintain pressure.

I am just preparing, if it came to it, how to drain down the boiler system.

 

[seco services]

If the problem is the ev just drain below it.

 

[Stevecc]

Thanks. There is a filling loop with isolation valves on both ends just below the boiler. I could disconnect the one end of that and drain the boiler that way then

 

[FiremanT]

Thanks. There is a filling loop with isolation valves on both ends just below the boiler. I could disconnect the one end of that and drain the boiler that way then

Assuming the DCV is fitted on the correct, ie. mains water, side