I also have a Microbore system. Does the whole central heating system have to be drained before removing a radiator? Or can you somehow shut off both the "water in" and "water out" valves on the radiator? Seems easy enough to shut off the "water in" valve but the "water out" valve is less obvious. After removing the protective cover there is a nut which seems completely tightened. When you loosen it, water begins to drip out. It seems strange that the nuts are tightened to capacity since surely this suggests that the water is prevented from leaving the rad?
Also, on the microbore system there doesn't appear to be a master drain cock since there is no exposed pipe other than the thin 10mm pipes going into each rad. However, each of the rads on the ground floor seems to have its own drain cock. Should i simply drain down the system through one rad?
The return pipe shouldn't be fully closed but it may not be far off, it is the lockshield valve for balancing the system. Was that rad working ok?
There are individual drain points because each rad is dropped down on its own individual circuit from the main manifold, so one rad downstairs will drain all the upstairs rads and the drop it is on, but all the other downstairs rads will require draining each drop at a time.
Thanks Olski. That makes sense, maybe it wasn't fully closed, just gave that impression. The rad was working fine so maybe it just didn't need to be opened too much. If that is the case, if i were to tighten it completely, would i be able to remove the individual radiator without bleeding the whole system?
I have noticed that there is actually one radiator downstairs without a drain cock. Could it be that this one isn't connected to any other radiators?
Thanks for this help it's a godsend - there's absolutely nothing about removing microbore rads on the net!
Sorry to harp on about this. I just want to get this cleared up once and for all.
Can I definitely remove radiators on a microbore system without draining the who C/H system down? (as in by tightening the lockshield and inlet valve).
The only reason im checking this is because a plumber told me that there was absolutely no way id be able to remove any microbore rad without bleeding the system first. Yet other people tell me i can. I'm scared of what might happen!
If your valves can be closed completely i.e. they are working properly and not knackered, then yes, close the valves and remove the rad. I echo the earlier caution on 10mm copper pipes; they bend and crack VERY easily, do not put any pressure on then. When you are undoing and subsequently tightening the valve connections for removal and refitting, use a tap spanner (or similar, straddled either side of the valve body) to counteract the force you are applying to the valve nut i.e. no force on the pipe; be warned, it WILL break if you let it be the only thing taking the strain of the pressure you use to open / tighten the valve nut.
Also, make sure you are turning the valve nuts the correct way otherwise you may be trying to tighten when attempting to remove and may think they are seized. Remember that the nut is actually part of the radiator fitting and not the valve, if you hadn't sussed this you would be trying to turn it the wrong way.
i have a downstairs toilet with a micobore radiator and want to change it to a towel rail. i cannot find a drain tap for the system, do i need to drain the whole system if so how? or can i create a trap in some way? or would it be adviseable to freeze the 2 pipes bearing in mind i only have 2 inch of pipe coming out of the wall. any help would be appreciated.
If your system is NOT sealed and has an unsealed central heating cold tank in the loft then this may be of help. Drayton make an item called an Easy Drain Kit.
This kit basically comprises 2 tapering plugs. One of these plugs is used to seal the expansion pipe to the loft tank and the other is used to seal the feed pipe from the loft tank. Now providing only 1 break is made in the system only about an egg-cup full of fluid will escape before a vacuum is created and this prevents further fluid escaping. NOTE that if you just cut a pipe then you have made 2 breaks in the system as BOTH ends of the pipe are open. I have used this gadget to to remove a radiator without having to anything else on numerous occasions.
See the web page below for more info and full instructions on how to use the Drayton Easy Drain Kit htttp://www.invensyscontrolseurope....roductsServices/Drayton/Ancillariesandspares/
with your method i can block uo pipes as said shut off both present rad valves remove exisisting rad fit towl rad remove one old valve with slight water discharge and fit to new valve on towl rail lock this valve off and open other to fit
will try to word that better.
block pipes in loft as said, lock down both valves on rad to be removed and seperate from rad, drain rad contents, fit new towl rail, remove one valve from microbore pipe and fit to rail, then lock this valve down, remove the other valve from microbore pipe and fit to towl rail?