I have a c/h problem . only half my rads work . hot water going out of boiler warm water coming back in .I have 8 rads in my house over 3 floors only 4 are working . pipe cold under rads that don't work . the hot water seems to be circulating the system but missing some of the rads ?
check the radiator valve are open some time thermostatic valves get stuck in close position
If the valve can not be open you may require a plumber to change the valve
either way it would be wise to have it looked at
http://www.emergency-plumber.eu/
andrew t
February 2015
On your hot radiators close off both the inlet and the outlet (lock shield) valves.
On the cold ones open both valves - I suspect the colder radiators have their outlet valves closed so water can't flow out of them and consequently can't flow into them - i.e no hot water is going to them because no water can come away from them .
But I'm not qualified to offer this opinion. A better person might come along and provide a more realistic answer.
Good luck...
January 2015
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