have just had gas central system upgraded [ new condenser boiler, thermostats on rads etc] but now I have a constant noise like a duh, duh, duh, which seems to be coming from thr radiator/pipes. Called out the plumber but he said it was just the pipes contracting as they heated up or cooled down but I've never had the problem with my old system and the pipes have not been changed. Help please the noise is driving me mad!
thank you Lemrac
thank you Lemrac