thats thermastart on rads but if you want change room start you can have two wire and three wire its work like switch on and off one is live other carry power to boiler on three wire one is natural one carry power to boiler,natural is blue,if you got two wire one just connect in and out one not blue ,cover blue with tap
ltd
May 2013
its pin in middle that need clean spray WD40 and pull pin out and push in slow not all only part ,that will let water in if you want replace ,than you have to drain system
ltd
May 2013
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