How long top drain down open system?

26 Feb 2007
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United Kingdom

I'm draining down my open CH system, and have opened the bleed valves upstairs first. I tried opening the downstairs bleeds but there is still a bit of water coming out. The small F+E tank in the loft has had its ballcock tied up.

It seems to be taking ages (45 mins so far) - is this normal? Do I just need to be patient and wait - the water coiming out of the hose (attached to drain cock on downstairs rad) is only trickling.

There are 5 rads upstairs and 3 downstairs
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Sounds like the drain off point is blocked or the rubber washer has come off the end of the bit you unscrew. Put plastic dish & plastic sheet under D O P take off hose, is it still trickling/ If so get small electricians screwdriver and poke up end. If this don't work unscrew completley and put screwdriver up this bit. be prepared for gush of water if it was blocked.

You may need a new drain off washer fitted before reassembly.

Draining down can sometimes seem to take an age.
When you (eventually) drain it, consider fitting these to your downstairs radiators instead of ordinary lockshields (especially on rads that are near an external door that you can poke a hosepipe out of). They will make it quicker and easier next time.

If the downstairs rads are supplied by pipes that come down from the ceiling, you will need one on every downstairs rad.

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Thanks John, the downstairs rads already have these (it is one of these I'm draining the system from).

Thankfully, it seems to have stopped trickling, so no for the hard (for me) bits ....

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