i assume ur rads r fitted with trv,s (thermostatic radiator valves) if so u could try closing all th other rads that are working by simply turning the trv to 0 or *.if its an airlock this should push the air round the 2 rads that arent working an solve the prob.if this dosent cure it then its possible that th small pin in th trv valve has stuck,common problem with older trv,s especially danfoss.remove th valve head (the big white plastic thing with numbers on)and below it u will find a small pin.gently with a pair of pliers ease th pin outwards but be very careful not to pull it all the way out or a small flood may occur.if this still dosent work it could be posible that if work has been carried out lately on your central heating system the plumber may hav got 2 flow pipes and 2 return pipes mixed up resulting in 2 flows feeding one rad and 2 returns feeding the other!this will cause both rads to not work,in which case consult a QUALIFIED plumber/heating engineer.in any case i would always advise to contact a professional in the first place,thats what were here for.hope this was of some help.
kennyboy
December 2007
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