you mean ideal make with header tank to fill water ,shut water from header tank there is stop valve ,or shut water from main coming in property ,drain from drain out point at lower point from rads ,open air vent on rads as water drain out star from top ,than ground floor ,when refill shut air vents open header tank water in let .open air vent one by one to take air out ,open big nut on pump one turn than close
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July 2013