Draining CH Rads

[kevhky]

Hi Folks

I need to drain complete ch system (Combi boiler), Which is the best and easiest way with the least mess.

The lowest rad in the system is right near front door that leads onto garden.


Any help will be much appreciated

 

[chrishutt]

Why do you need to drain complete system? It's usually sufficient just to drain the section to be worked on.

 

[keego]

There should be a drain off valve either on the lockshield valve or on the pipework below it, if there isn't then things are a little bit more difficult.
If you have radiators with a 1/2" plug & vent then you could shut down the rad & remove it & fit a 1/2" BSP drain off to that.
DON'T BE TEMPTED TO USE THE BLOW OFF TO DRAIN IT!!!!

 

[kevhky]

I need to move a rad approx 2" to the left i need to extend the current pipe work to connect to the new position, so surely when i remove the valves from the pipe water in the system will ruin the carpets, The rad to be moved is upstairs

Kevin

 

[chrishutt]

Then you don't need to drain the boiler itself, just the pipework and rads, but only down to the level that you're working. You can close the isolating valves on the flow and return pipes under the boiler, if the boiler is above the level of the work (although some will say don't because the valves will leak, which they might but probably won't). Also you can avoid draining most of the rads by closing off the valves at both ends.

 

[keego]

If it's a Worcester then the valves will start leaking as soon as you think of turning them off, personally I would go for a drain down after all it's combi system, it's not as if you're going to be hours getting rid of airlocks like a gravity system.

 

[kevhky]

The combi is above the rad in question

how can i get water out of the rad and pipework easily with little mess (ill turn valves off on other rads at same height as rad im orking on)

Do i open bleed valve and drain off that way or is there an easier way

Kev

 

[Al-Glasgow]

sorry to hijack a thread, hope you dont mind,

Combi system, 6 months new install,2 bed semi.

If you drain an upstairs bathroom rad, then drain pressure from cust.control valve, and you get a light yellow is this inhibitor ?.

Al