Steam Radiator Noise Home › Forums › Public Forums › General Plumbing › Steam Radiator Noise This topic has 1 reply, 2 voices, and was last updated 23 years, 11 months ago by SylvanLMP. Viewing 1 reply thread Author Posts 6 Feb 2001 at 12:58 am #274579 MasterPlumbersKeymaster How do you prevent loud hissing from radiators in an apartment? Are you supposed to drain them? 6 Feb 2001 at 1:23 am #289979 SylvanLMPParticipant No you do not drain a steam vent YOU have a qualified person replace the air vent with a good quality one Author Posts Viewing 1 reply thread You must be logged in to reply to this topic. Log In Username: Password: Keep me signed in Log In