What are the limits of the Pexal system?
The extreme operating condition is 95°C at a pressure of 10
Bar.
The system can support a temperature of 100°C for a short
period (malfunction time).
Is it preferable to use pipe lengths or coils?
There is no difference in technical terms between pipe lengths
or coils. The choice is left to the installation technician depending
on the geometry of the system: the coil is more economic for a
given length and diameter.
Is it preferable to use screw-on or press-on fittings?
First of all it must be said that both types of fittings give
the same seal guarantee, if fully tightened and correctly pressed.
The installation technician in Italy and in Western Europe prefers
press-on fittings, since the pressing operation is performed by
a machine, therefore possible faults due to the human factor are
avoided (refer to the case of installation using screw-on fittings).
The use of press-on fittings implies an investment to purchase
the necessary equipment, however this is rapidly amortised by
the speed with which installation is performed using the press-on
system.
Can the jaws for the Pexal press-on system be fitted on other
crimping machines not sold by Valsir?
Yes! There is complete interchangeability among the jaws and
crimping machines sold, the Valsir jaws for the Pexal system can
be fitted therefore on competitor crimping machines (excepting
of course for the systems that do not adopt the press-on solution),
and the jaws manufactured by competitors can be fitted on Valsir
crimping machines.
Which flow comparisons can be made between the Pexal system
and the other sanitary systems?
PEXAL COPPER PEX STEEL PP-R
D. 14x2 D. 12x1 D. 15x2.5 3/8"
D. 16x2.25 D. 14x1 D. 16x2.2 1/2" D. 20x3.4
D. 26x3 D. 22x1 ¾".
Is it possible to use valves and manifolds produced by other
manufacturers with the Pexal system?
Yes! Use of the specific Valsir adapter (art. 1075) is required.
At which minimum temperature can the PEXAL pipe be used?
This depends. The minimum operating temperature is associated
with the "non-freezing" of the liquid contained in the
system. In the case of external installations, where low temperatures
are foreseen, it is advisable to insulate the pipe with special
material (a circuit discharge should be provided, if possible).
Can the Pexal system be used to distribute drinking water?
Yes! In this regard we can exhibit the relative certificate issued
by the Institute for Hygiene of Padua University.
Can the Pexal system be used to distribute fuel gas inside buildings?
This depends on the regulations that are applicable in each country
governing the installation of gas systems. This is not possible
in Italy, in other countries (for example Australia, where the
Pexal system is used to transport Gas) the regulations do provide
for this.
Can the Pexal system be used for air-conditioning systems?
Yes! Provided the fluid is water, that the water temperature
lies between 0 and 95°C and that the operating temperature
is less than 10 Bar.
How can the expansion be calculated?
There is a formula:
Expansion = 0.026 m/m°C x pipe length x temperature change
where 0.026 m/m°C is the expansion coefficient.
For example: assuming water circulates inside a pipe and can reach
a temperature of 70°C and the installation temperature is
equal to 0°C; the pipe length is 5mt., we can therefore replace
the data in a formula:
Expansion = 0.026 m/m°C x pipe length x temperature variation
Expansion = 0.026 x 5 x (70 - 0) = 9.1 mm.
I have to install a system complete with inlet (vertical columns,
bathrooms, kitchens, heating systems), is it possible to use Valsir’s
consulting service?
Yes! We have a Technical Department capable of providing every
kind of recommendation.
Should the Pexal pipe be protected in any special way when buried
in the masonry?
This is not essential, however, protection using heavy paper
or corrugated cardboard causes no harm. It is important, on the
other hand, to cover the fittings using heavy paper, especially
if the stabilising material used is rich in lime.
What kind of threads are adopted on the Pexal system fittings?
The threads are standard and are of the "conical gas" type complying with the ISO 228 standard.