Draining\Filling central heating

Biggie

Hi,

Need to move and change a radiator in the living room.

I have a pressured gravity feed hot water system. I have a pressure dial above the boiler which goes up as I fill the central heating system and a tap to let the water drain out.

Would I need to drain the whole system for a radiator change ?
also i'm not sure I can refill with inhibitor ?

bobinbognor

Hi, Sounds like you have a combination boiler with a pressure gauge. If so you will have to isolate the incoming fresh water. There should be an isolating valve for you to do this. Find the lowest drain point in the system, it should have a square shaft and a push-on hose connection. Push on a suitable hose, probably 1/2" and run it to a drain outside the property. Don't let it run to ground on a lawn because any inhibitor in it may kill the grass. Open the square shaft and let the water drain off. You dont have to empty the whole system but how do you know when the radiator is empty? You don't, so drain it all off. Be careful draining from the boiler because the radiator may be lower and could remain full. You don't want to ruin your carpet or flood your laminate floor. Dont forget to also isolate the gas and switch off the electric power. You dont want the boiler to come on when its empty. Take care!

Biggie

thanks for the response bobinbognor.

Just to clarify it's not a combi-boiler but a pressured gravity fed system (i.e we have a red pump in the attic)