1 Pipe Radiator Pitch Repair
Most repairs on a steam system require a basic understanding of physics. A single pipe steam system is the simplest to work with.
If you have such a system you'll see that your radiators only have one pipe on them. This single pipe carries the steam into the radiator and allows the condensed water(condensate) out. If you look below you'll see a diagram showing a properly pitched radiator. The water is flowing down the pipe smoothly and the steam is filling the radiator quietly.
If you look at the diagram below you can see an example of an improperly pitched radiator. The water can't flow out of the radiator until it begins to pool at the bottom. As it flows down the pipe the steam will begin to interact with the water and catch the water as it seals the area of the pipe. As this happens the steam builds pressure until it gains enough pressure to throw the water up the pipe and out of the way. This then "hammers" the pipe or valve and makes a racket.
So, how do we fix this problem?
It's incredibly simple. I like to use 2in washers under the feet of the radiators in order to change the pitch. You can get them at any hardware store and can put them under the feet of the radiator on the side away from the supply line to the fix the pitch. Using a level you can set the pitch so that the bubble is just beginning to touch the line on the side of the radiator away from the supply line.
No more banging pipes!