PER fittings are components designed for the implementation of a plumbing network in cross-linked polyethylene (PER). This material stands out for its convenience and resistance to wear. In new construction or renovation projects, the accessory is used in both heating systems and water supply systems (cold or hot).
Installations in cross-linked polyethylene (PER) are practical and accessible to everyone, because this material does not require:
- any brazing (a welding technique involving the handling of plumbing parts at high temperatures);
- any specific plumbing knowledge;
- more than a few tools to assemble the various pipes making up the network.
Used in sanitary plumbing and heating, PER fittings can be either:
- slip type, mainly present in heating systems due to their strength and reliability against leaks, but still require some techniques and special equipment (crimping pliers and flare pliers);
- crimp type, allowing for the permanent installation of PER pipes in a network (the crimping pliers deform the accessory and integrate it into the pipe system in a permanent way);
- compression type, easy to dismantle and suitable for large diameter pipes, fixed with a metal ring (under the action of the nut, this element ensures the connection by crushing the PER pipe onto the fitting);
- automatic. This type of accessory is very easy to install, but is quite fragile. It closely resembles the compression fitting. However, here, the connection is ensured by a clip locked with a nut.
The characteristics of the accessories used depend on the plumbing configuration. Thus, in a model:
- compression, 12 mm pipes are suitable for a thread diameter of 3/8 - 12/17 or 1/2 - 15/21 inches, the threading will also be 1/2 - 15/21 inches on a network of 16 or 20 mm, against 3/4 - 20/27 inches on an installation of 25 mm in diameter;
- slip, a thread of 3/8 - 12/17 inches will be adapted to a network of 12 or 16 mm, against 3/4 - 20/27 inches for pipes of 25 mm;
- crimp, threads of 3/8 - 12/17 and 1/2 - 15/21 inches correspond to PER installations of 12 and 16 mm in diameter.
PER fittings are chosen according to the pipes composing the installation. These dictate the different characteristics of the accessory (diameter, type of connection, etc.). It is also important to consider the type of fitting adapted to the existing network or to be installed in the building.