Draining a micorbore system

[bengasman]

Flat with combi and half a dozen rads on micorobore. To say it is badly corroded and sludged up is putting it mildly; complete botch install.
There is a drainpoint under the boiler. Unfortunately the bottom of the boiler is about a metre above the top of the highest radiator. To make matters worse, the flow and return go straight up into the ceiling, and all the rads are on drop downs.
Rad valves are hard to turn and look highly suspect.
How do I empty this system without the risk of spilling buckets of gunk on the carpet?

 

[mickyg]

If you have any 15or 22 at low level you can use a self cutting tap, then repalce with drain off once finished, otherwise drain lowest rad, turn rad valve 90deg, connect hose to rad valve using whatever fittings required, usually a bit of 15mm and 1/2" nut and olive( but depends on valve) and drain. If its all on drops, repeat once finished might be worth fitting some tails c/w drain.

 

[kevplumb]

now bear in mind this is only a suggestion


can you shut the rad valves (old towel on floor)

get a hose sorted freeze the pipe coming in takes app 1 min undo it and stick end in the hose

you can carry the rads out to empty them

 

[bengasman]

If you have any 15or 22 at low level you can use a self cutting tap...

Got one of those as an emergency option in the toolbox, rads piped up in micorbore all the way into the valve.

 

[bengasman]

...can you shut the rad valves (old towel on floor)

get a hose sorted freeze the pipe coming in takes app 1 min undo it and stick end in the hose...

That is part of the problem, I don't trust the valves, they all show signs of leaking around the stem, all the ones I tried don't turn as you would expect, and some are actually weeping.
The main reason to drain the system is to replace the valves.

 

[kevplumb]

=======================================================

ben could you not freeze the valves as well and poss cap inlets

faff on i know but

 

[namsag]

EH what about rolling the carpets back so no sh#te can get on them.
Has someone hacked into bengas`s account why would someone who installs heating have to ask such a basic question .

 

[bengasman]

...ben could you not freeze the valves as well and poss cap inlets ...

That is actually pretty much what I am trying to avoid.
Apart from hating freezing, I don't trust the valves, or the rads, or the pipes. I would not be at all surprise to find they are prevented from leaking out of completely mangled joints and threads by a combination of teflon tape, gaffa tape, lsx and plumbers mait. This job, in fact the whole flat shows all the signs of a micro budget refurb. Budget boiler, no falsified benchmark, cheap old rads, cheap wonky valves, bonding on the gas but not on the water, no stop cock, roomstat that I am sure has never worked, electrical cables wrapped around the gaspipeetc. etc.

The best solution I have come up with so far is blowing the water out with compressed air via the bleeding nipple.

 

[bengasman]

EH what about rolling the carpets back so no sh#te can get on them.

Don't trust the valves or the pipes, floor is wonky and any spillage that is more will end up in the flat below that has recently been tarted up by a bunch of polish builders, and I doubt very much that the ceiling will resist more than a cupful of water.

Has someone hacked into bengas`s account why would someone who installs heating have to ask such a basic question .

It is a very basic question, what makes is exceptional is the combination of botches throughout this flat as well as the one below.
I am trying to help a friend out, if this was a normal job I would have run as fast as I could. The guy is really to good for this world, and was massively ripped off by another plumber he called in when I was stuck on a job, and he couldn't wait, as water was coming through the ceiling. But that is a different story.

 

[bengasman]

blah blah blah

Untitled

• bengasman
• 7 Sep 2009
• 11

 

[namsag]

Now i know its been hacked,,,, Blow it out bleed nipple with compressed air.
What the fek

 

[bengasman]

Now i know its been hacked,,,, Blow it out bleed nipple with compressed air.
What the fek

open drain valve, wait til water stops coming out.
take bleeding screw out and connect to air source.
open rad valve and blow air in; watch water coming out drain point.

 

[mickyg]

drain lowest rad, turn rad valve 90deg, connect hose to rad valve using whatever fittings required, usually a bit of 15mm and 1/2" nut and olive( but depends on valve) and drain. If its all on drops, repeat

if your replacing them what does it matter if they leak a bit?

 

[namsag]

Eh its a combi so pressurised system close auto air vent release pressure out of bleed nipple .
System is then vacumed up

Take necessary precautions to protect carpet best rolled away but plastic sheeting and old bath towels sufficient.
Change each valve , one a time very tiny bit if any water will come out if twin entry valves put d/cock in other end of rad at same time if seperate valves use the ones with built in d/cock.
After finishing job you can drain and flush properly

 

[bengasman]

drain lowest rad, turn rad valve 90deg, connect hose to rad valve using whatever fittings required, usually a bit of 15mm and 1/2" nut and olive( but depends on valve) and drain. If its all on drops, repeat

if your replacing them what does it matter if they leak a bit?

Very black gunge.
And if I was SURE it would only be a bit, I would chance it with plastic sheets and towels. But I am not sure, and I don't trust anything about this system to work as it should.