I was reading the installation instructions for hot water (hydronic) baseboard heating sections. It says to consider using a special coupling between long sections of baseboard to allow for thermal expansion of the pipe:
So obviously they are recommending a specific product of their own, and maybe there are alternates from other manufacturers.
But my first thought was whether using a push to connect fitting for this joint would offer any benefit? Some of them are plastic, others metal, but all seem to allow for more flex than a soldered joint would. Since I assume the reason to allow for thermal expansion is mainly to reduce noise, I wonder if the PTC fitting would do the job or at least be better than a soldered joint in terms of noise reduction?