DIY Doctor UK DIY Forums

Since turning heating on several weeks ago, the rads have been falling like flies, a couple were cold, bleed them still cold, now the 2 small rad that do not have thermostats are working fine,both hot(bathroom &wc) as for rest of bungalow now only 2 rads with thermostats,are working, all the rest are cold.
Boiler new 18 months ago (Worester Combi Boiler). Spoke with fitter yesterday....seemed not interested, said could be pump, air lock or thermostats, he will try and come out next week.
I need advise on what to say etc. Am get very concerned now when I run off hot water the pipes seem to be surging. I spent good money on replacing the boiler, the old one was 25 years old....yet never had any problems with rads warming up. Out of 7 rads only 2 working.
My hubby has no idea on these matters, and I am getting quiet concerned that this is something major.

Check boiler pressure, should be between 1.0 and 1.5 and also vent radiators, as if it wasn't filled properly when installed it could be full of air.

Air locks on pressurised systems are very easy to clear, if venting the radiators doesn't work, or the radiators are full of water - turn off the radiators that are heating and see if the others will push through.

Also the pins on the TRV valves could be sticking.