strong plumbing pliers should do trick.remove plastic control head.unscrew chrome nut.replace with similar one.plumbers tool box shud have spare.
diy expert,heating engineer, December 2012
Thank you Kash. Successfully off - we and the christmas tree are very grateful!!
V Cassidy, December 2012
turn it to 5 or full i cant remember if it has numbers on there. then just unscrew the silver clip under the head screw it anti clockwise and the head will then lift of. if the silver clip does not unscrew u may need the help of some large pliers to loosen it
kash, December 2012
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I can answer this question...
how can I remove Westherm radiator valve cap to un-stick the control?