Clicking Radiators - Main vent to blame?

gerrys

Wife and I moved into our first home about 2 months ago, and I've slowly been diagnosing problems in my first steam heating system. I've rid the system of the louder banging by replacing some old Hoffman vents with Gorton 4s and siphoning off some of the dirtiest water in my boiler (flushed about 30 gallons through it).

With the new installed vents, however, there is a less loud but still annoying clicking coming from the bottom of two of the upstairs radiators. This is coupled with the vent in the last radiator in the chain working extremely hard – I can hear a lot of air rushing to escape from this vent.

My hunch is that the archaic Hoffman 45 main vent in the basement is clogged. Do these symptoms sound like that might be the case? I'm admittedly very new to this stuff, and would like some more confidence before I go out and drop more money on vents.

KC_Jones

Getting venting/balance correct starts with the main vents in the basement. I don't believe that Hoffman is even a main vent, so most likely woefully inadequate.

What size and how long are the mains? We should be able to recommend an amount of main venting that makes sense.

The ticking could be expansion noise. In these systems the temperature differential is such that there needs to be room for expansion. If there is not, noise will occur. So none of the pipes should be in direct contact with wood. Some adjustments may be needed If that's not possible, some cut up pieces of milk jug can be pinched between the wood and metal which allows things to slide quietly.

That banging most likely isn't fixed, even though it may be quieted down. While putting smaller vents on the radiators may stop the banging the cause of the banging is water being where it's not supposed to be. To that end all radiators need to be properly pitched towards the supply, and all the horizontal piping need to have proper pitch and no sags. The reason the vents can sometimes help with banging is because you slow the advancement of the steam down that it isn't moving as fast to cause the banging. Good for banging bad for heating and efficiency.