Heating engineer
Installation, use and maintenance manual – Caldaia 55.1 and 100.2 Tech
23
3
Gas pipes sizing
The gas pipes must not cause excessive pressure drops and, con-
sequently, insufficient gas pressure for the appliance.
Supply gas pressure
This appliance is equipped for a maximum gas supply
pressure of 50 mbar.
The appliance's gas supply pressure, both static and dynamic,
must comply with Table 3.4
p. 23, with tolerance ± 15%.
Non compliant gas pressure (Table 3.4
p. 23) may
damage the appliance and be hazardous.
Table 3.4
Gas network pressure
Product category
Countries of destination
Gas supply pressure [mbar]
G20
G25
G25.3
G30
G31
II
2H3B/P
AL, AT, BG, CH, CY, CZ, DK, EE, FI, GR, HR, IT, LT, LV, MK, NO, RO, SE,
SI, SK, TR
20
30
AT, CH
20
50
HU
25
30
II
2H3P
AL, BE, BG, CH, CZ, ES, FR, GB, GR, HR, IE, IT, LT, NL, LV, MK, PL, PT,
SI, SK, TR
20
37
AT, BE, CH, CZ, DE, ES, FR, GB, HU, NL, SK
20
50
AT, CZ, DE, NL, RO
20
30
II
2ELL3B/P
DE
20
20
50
II
2Esi3P
FR
20
25
37
II
2E(R)3P
BE
20
37
II
2E(S)3P
20
37
II
2E3P
LU
20
50
II
2E3B/P
DE, PL, RO
20
30
II
2L3B/P
RO
20
30
II
2L3P
FR
25
37
RO
20
37
II
2EK3P
NL
20
25
30
II
2EK3B/P
20
25
30
I
2EK
20
25
I
2ELL
DE
20
20
I
2E(S)
BE
20
I
2E(R)
20
I
2Esi
FR
20
25
I
2H
AL, AT, BG, CH, CY, CZ, DK, EE, ES, FI, GB, GR, HR, IE, IT, LT, LV, MK,
NO, PT, RO, SE, SI, SK, TR
20
FR
20
HU
25
I
2L
FR
25
RO
20
I
2E
DE, PL, RO
20
I
3B/P
AL, AT, BG, BE, CY, CZ, DE, DK, EE, FI, FR, GB, GR, HR, HU, IT, LT, MT,
NL, NO, RO, SE, SI, TR
30
PL
37
AT, CH, DE, SK, CY, CZ
50
FR
50
I
3P
AT, BE, CH, CZ, DE, ES, FR, GB, HU, IS, NL, SK
50
AL, BE, BG, CH, CZ, ES, FR, GB, GR, HR, IE, IT, LT, NL, LV, MK, PL, PT,
SI, SK, TR
37
AT, CZ, DE, NL, RO
30
The appliance gas supply pressure, both static and dynamic, must comply with the values in the Table, with a tolerance of ± 15%.
Before proceeding with the construction of the system, the in-
staller must:
▶
Check that the gas used corresponds to that for which the
appliance has been designed (see nameplate).
▶
Check that the flow rate of the gas meter is such as to ensure
the simultaneous use of all the devices connected to it.
Although it is normal for the inlet pressure to decrease
during the operation of the appliance, it is important to
check that there are no excessive fluctuations in the inlet
pressure. In order to limit the extent of these variations, it
is necessary to appropriately define the diameter of the
gas inlet pipe to be adopted based on the length and
pressure drop of the pipe itself, from the gas meter to
the boiler.
If fluctuations in the gas distribution pressure happen,
it is advisable to insert a special pressure stabiliser up-
stream of the gas inlet to the boiler. In case of LPG
supply, all necessary precautions must be taken to avoid
freezing of the combustible gas in case of very low ex-
ternal temperatures.
