The section covers the most frequently asked questions, sub-divided per topic.

General information

Yes. It is, however, necessary to ensure that transport of the fluid in question is not prohibited by specific regulations (such as fuels in general), and that, where transport is permitted, its concentration is compatible with each component of the system, pipe/fittings/gasket, verifying this in the respective technical guides.

Follow the instructions in the technical guides regarding assembly of the system, insulation and clamping, in the event of exposed systems.

No. You need to pay close attention to the liquid you use for maintenance. Generally, manufacturers of system cleaning fluids give generic compatibility with PPR/PE plastic piping.  It should be considered, however, that a system is composed of both piping and fittings in brass (OT CW617N) with gaskets. Therefore it is important to check the technical data sheet of the product to be used and no incompatibility with all these materials should be reported.

Yes. The test procedure of the system is outlined by legislation in force. It is therefore necessary, before installing floors, screeds or other elements, with the system still accessible and visible, to carry out testing, according to the instructions outlined in the Prandelli technical guides.  

When use, storage and installation do not follow the instructions outlined in our technical guides. It is very important for a system to be installed entirely with Prandelli pipes and fittings.

It depends on local legislation in force. In Italy yes, enforced by energy saving legislation (Law 10/91 DPR 412/93). In addition to this, good insulation allows the system better efficiency and better preservation.

By means of a standardised table (according to Law 10/91 DPR 412/93), which establishes the required thickness according to the size of the pipe, the position of the system and the thermal conductivity of the insulation.


The Coprax system consists of random copolymerised polypropylene piping and fittings according to UNI EN ISO 15874. The characteristics of the system make it suitable for plumbing, heating and sanitary installations in the most diversified forms (see guide or data sheet) and with remarkable reliability over time. The special feature of Coprax is the assembly technique, which is carried out by fusion welding. As a result, the pipe and fittings become a single body, a feature that makes Coprax a highly reliable system, excluding problems that may arise from potential leakage points.

Check the temperature (260 °C) of the polywelder before proceeding with welding.
-ensure that there are no drops in voltage, which could compromise proper functioning of the machine.
-pay close attention to the pipe surface: there must be no trace of oil, dust, earth, grease, or other substance.
-follow the instructions on the Prandelli technical guide for welding times in relation to the size of the pipe used.
-at the end of the operation, a plastic "bead" must be evident.
-wait for the necessary (cooling) time before handling.

The Coprax pipe is entirely made of PPR material. Prandelli Coprax Fibra is instead made of three layers equally divided in thickness (1/3). The inner and outer layers are in PPR, while the central layer is in PPR with fibreglass. This ensures the fibre pipe has lower thermal expansion. All other characteristics remain identical.

Like all plastic piping, low temperatures can be harmful because they can create ice internally, and consequently cause a rupture due to the resulting increase in volume. Furthermore, low temperatures make the pipe more fragile, so greater caution is needed in handling and installing the material under such conditions.
It is appropriate to insulate (for insulation thicknesses refer to the standard table in the technical guide), use anti-freeze (not for pipes for drinking water use), and for parts of systems exposed to risk of impact, protect with clamps or other elements. 

No. Coprax fittings are made by fusion (hot moulding), together with inserts. In the event of breakage, the entire coupling must be replaced.


Tuborama is a cross-linked polyethylene pipe complying with the UNI EN ISO 15875 standard, suitable for the construction of plumbing, heating and sanitary installations. The high quality standard of the raw material used and the reliability of the technological process make Tuborama a product that responds with great effectiveness to the most diverse system requirements (see guide or data sheet). The creation of joints using mechanical brass screw fittings also makes the installation technique particularly simple.

Yes. The high flexibility of PE-X is an essential feature to install a state-of-the-art system of this type without any particular difficulty. In the application of underfloor heating panels, the good oxygen impermeability of the material used to create this pipe is particularly significant. In any case, to overcome this phenomenon, Prandelli offers a type of pipe - Tuborama O2 stop PE-XB - which has the same basic characteristics as the "classic" Tuborama, with the addition of total impermeability to oxygen.


The Multyrama system is characterised by a multilayer pipe made of PE-XB material, while the Tris Up pipe is characterised by a multilayer pipe made of PE-RT material, both complying with UNI EN ISO 21003, produced with modern technologies. 
They have the prerogative to simultaneously combine and exploit the characteristics of plastic and aluminium. They are in fact pipes made of two layers of polyethylene (Multyrama cross-linked and Tris Up cross-linked), coupled to an inner layer in aluminium. The joints can be installed using brass fittings, compression type press fittings or screw fittings with a nut. Their characteristics and resistance allow the installation of various types of systems (see guide or technical sheet).

The Multyrama pipe is in cross-linked polyethylene, while the Tris Up pipe is in cross-linkable polyethylene.

Yes. The pipe has an aluminium layer that makes the pipe impermeable to oxygen.

Yes. The pipe needs to be calibrated because in the pre-assembly cut it could become ovalised and make it difficult or even dangerous (dragging OR out of place).

The maximum use temperature is 80°C (refer to the table of the "application classes”, outlined in the technical guide). The pipe also withstands higher temperatures, but for a very short time.   During the life of an installation (50 years) malfunction situations may occur, with tolerances up to 95/100°C for a maximum of 100 continuous hours.

When a burr appears on the stainless steel bushing of the press fitting (PF/PFM), that is, a steel facing in the area where the matrixes close.


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