I have a 1930's 4 bed house with 10 radiators, three of which are in a two story extension dating to somewhere in the 70's as best I can tell. I have no idea of the age of the central heating system as a whole. The extension appears in general to have been built a bit on the cheap and contains 4 of the radiators - one upstairs, one downstairs, one in the kitchen and one in the downstairs bathroom.
It's these last two which are causing me the most concern as they are completely cold at all times and are starting to cause damp problems in both the kitchen and bathroom.
The other radiators in the house appear, some to be slightly affected, others completely unaffacted.
My first thought was of course to bleed the radiators, but the one in the bathroom produces a very high presssure jet of cristal clean water if the bleeder plug is completely removed.
As it clearly has water under pressure getting to it, and that water is clean (presumably indicating it's not gunked up??) I would have thought it should be getting hot water through to it... or else where's the pressure coming from??
The radiator in the kitchen simply doesn't have a bleeder valve... so god knows how I'm supposed to check that for air voids.
Does anyone have any diagnostic tips or suggestions as to what I might look at doing to solve the problem?