Shut off the water at the feed & expansion tank, or turn off thecold feed if you have a primatic tank. Open the drain, open the radiator bleed points, then when water has stopped coming out of drain replace the valve and re-fill the system.
Ian
July 2009
to long winded to go through all that on here.
look in google.
hi-spec plumbing & heating (essex)
July 2009
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