radiators making loud rattling and banging noises. All aspects of plumbing questions and answers, help, tips and information

[soo]

new boiler,watertank,thermostatic radiator valves and pump fitted to system to increase water pressure flow. since it has been fitted every time the radiators reach the temperature where the thermo valves should shut the radiator down it makes an almighty racket. The cure so far has been to turn the thermo valves up ,but I cant leave the heating on when I go out or leave it on low during the night. Please help. :(

[richieplum]

From what you describe it sounds as though the trv's are fitted the wrong way round. Check the little arrow on them, or better still check whether the tail into the radiator has a 3/4" unionated fitting or a 1/2" nut and olive fitting. If a 3/4" union then they are not reversible and so direction of flow is critical. Most modern trv's are reversible, but you may just be the unlucky one who got the non-reversible type. If not reversible, the only answer is to drain and refit/reverse the connections. ie, fit the trv where the lockshield is and vice versa.