If you are experiencing banging, clanking or even really noisy pipes when you turn your slant fin baseboard heat on this could be one of a few different problems. First you will need to determine if this is air trapped in the heating system or if the baseboard heat was improperly installed. The first reason you could have noisy baseboard heat is because there is air in the heating system. When you have air in the heating system this will cause the water in the baseboard heat to sound like it is “rolling” in the pipes.
When there is not enough water in the heating system this will happen. To see how much water you have in your boiler you will need to look at the pressure gauge. Depending on what type of boiler you have will determine what the actual boiler pressure should be but most residential forced hot water boiler systems run at between 17 – 28 psi. If you find that you do not have any boiler pressure at all then you will need to add some water to the boiler using the fill valve that is located on the boiler.If you have never used an automatic fill valve on a boiler then you will want to be careful not to overfill the boiler. This is one of the main reasons you will have a noisy forced hot water heating system.
The second reason you could have a noisy piece of slant fin baseboard is because when it was installed the heating elements were not properly installed. The slant fin heating elements are not only supposed to sit on the mounting brackets but on gray plastic expansion clips as well. When slant fin baseboard elements get hot they expand, and in turn if the plastic expansion brackets are not on properly the heating element fin will rub against the mounting bracket and cause you to hear noise.
What usually happens is the plumber that is installing the baseboard heat moves these out of the way when soldering of trimming the baseboard and then they forget to put them back in the proper position. This is more common in new homes rather then old homes as well. You can easily get your baseboard to be quite by simply sliding the gray plastic clips from where the are now to underneath the fin but on top of the mounting bracket. This plastic stops the fin from making noise as the baseboard expands. and contracts. If all of your gray plastic clips are in the right position and you are 100% sure then chances are you have air trapped in your boiler and you will have to learn how to bleed your boiler and then do so to have quite pipes.