Heating and plumbing

September 21, 2017Blog Standard

Heating pipes

When talking about a heating installation, we often refer to the brand of the boiler, to the aesthetics of radiators and forget the importance of the pipes that make up the heating circuit. A bad dimensioning of pipe diameters, not taking into account the loss of load that occurs in the different sections of the circuit, can lead to poor performance in the radiators and even that do not heat.

There are many types of heating pipes but in this document we will only refer to two of the most used today, copper pipes and multilayer pipes.

Copper pipes

This type of pipe has been used for some time and came to replace the iron pipe. This development occurs for different reasons:

Copper is a material that remains much more stable in terms of oxidation compared to iron, this makes the pipes of this material have a better age over time.

Welding copper

Both the copper pipes and the assemblies of the same material are soldered with tin, unlike the iron pipes that are usually threaded. A well welded joint is more durable over time and has fewer problems of leakage than a threaded joint.

By the manufacturing process, the walls of the copper pipes are much thinner than those of the iron pipes for the same equivalent internal diameter. This aspect influences in an important way the weight of the material to be used facilitating its transport, cut and manipulation.

Copper pipe

Another point to emphasize is the aesthetic aspect, especially in installations seen. The outer surface of the copper pipes has a smooth surface and when painting a good finish is achieved. By supplying the copper pipes in rigid bars of low profile, it facilitates their installation just above the plinths, easily mimicking the surroundings.

Multi-layer pipes

They are increasingly used in heating systems because they reduce the risk of leakage and limit heat loss without the use of shells. Multilayer pipes are so named because they are composed of an inner tube of cross-linked polyethylene, an intermediate aluminum pipe and an outer cohesive polyethylene pipe.

Multilayer pipe

Due to their resistance to high temperatures, multilayer pipes are increasingly used in conventional heating and underfloor heating systems, but they also work well in cold water pipes. Its main advantages include the ease of bending, high durability, resistance to high pressures and minimal expansion, similar to that of copper pipes, although they are lighter than these.

The secret of the resistance of multilayer pipes is in the manufacturing process: a layer welding system which is completed with two adhesive intermediate layers. This ensures the tightness of the pipe and reduces installation time, since a single pipe can connect the boiler to the water outlet point.

Manifold on the other hand, if we use collectors with centralization of keys, it will allow us to install pipes without joints to each radiator reducing the risk of leakage and its consequences, so that multilayer pipes can be used in both hidden and in sight installations. In the latter case, the aluminum layer helps to maintain the shape of the tube, available in various diameters and resistant to corrosion.

The aluminum foil maintains the shape given to the tube during installation. Only the inner layer is in direct contact with the fluid (withstand temperatures up to 95ÂșC), so that the aluminum foil and the outer layer ensure that the tube does not lose its original appearance. These characteristics also contribute to the product being impermeable to oxygen and water vapor.

The multilayer pipe is normally supplied in rolls of 50 meters for recessed use or under pallet, but can also be supplied in more or less rigid bars for use in installations seen. However, its plastic finish, the thickness of the pipe and the striking size of the joints, compared to the installation.


Copper pipes are more suitable in the realization of seen heating installations, which although they have welded joints, are always visible to be able to detect possible leaks. Being a rigid material supplied in bars and with a thin thickness, its visual impact on the environment is moderate.

Multi-layer pipes are more appropriate for installations that are going to be recessed or concealed, as there are no joints, we completely eliminate the problem of leakage. The use of collector key centralization requires the use of many meters of pipe, but is compensated by the non-use of particularly costly connecting pieces.

Leave a Reply

Your email address will not be published. Required fields are marked *