Quick Question: Where to drain off central heating?....

[ambient]

Hi, I am planning on draining and refilling my CH today since I added some desludger solution a few weeks back.

There are two drain off points in my house, one is above the boiler (high up in the kitchen downstairs) and the other below the downstairs hall raditor (very low to the ground).

Can someone please tell me which point I should attach the hose to drain off as much of the CH water as possible? When refilling I obviously don't want the boiler pipes ot be empty as this can damage it (apparently??) so does that mean I should or shouldn't user the boiler drain off???

Many thanks in advance, you lengendary plumber experts...

(Cacking myself about ruining the lovely warm house that I have just managed to fix!!!!!!!!)

Oh and before you ask, I do intend to put inhibitor in when I refill.

 

[Breesey]

Use both!

You'll only damage the boiler if it tries to fire while system is empty so turn it and all your controls off/right down.

 

[ambient]

I've only got one hose so thats why I was asking which would be best. Anyone?

 

[Whitespirit66]

. Drain everything out of the highest point, then close the valve and remove the hose pipe. Repeat this process on the lowest drain off point.

Then Bob's your aunty's live-in lover!

 

[ambient]

Thanks for the reply, I've drained off from the boiler outlet and its pretty much finished now but opening up the bleed valves on the radiators down stairs and water still spurts out. I will try as you've suggested closing off the boiler outlet and then attaching pipe to the lowest point and draining from there. Thanks matey!

 

[ambient]

Thats working so just draining off the last of the water now. The water is absolutely filthy so I recon it'll need a good flush through.

Please can someone tell me if I can drop the stop cock so water starts entering the system with the radiator bleed valves still open???

(The idea being that water will come in, flow through and come straight out the outlet flushing through the system!)

 

[Breesey]

I've only got one hose so thats why I was asking which would be best. Anyone?

Oh sorry!! Thought that went without saying

 

[ambient]

I've just refilled the system and switched it all back on and every radiator is now working. Wicked, starting to feel like a pro at this CH game, glad I didn't shell out to have someone else do it!!!
Really appreciate the help everyone, I must say this is one excellent and helpfull forum. Thank you very much.