Gas System Connection; Discharge Of Exhaust Flue Products Via A Draft Hood; How To Achieve The Nominal Thermal Capacity - Eurofrequence Minima Serie Instructions Pour L'installation, L'emploi Et L'entretien

2.3

GAS SYSTEM CONNECTION

- The unit should be supplied with gas having the characteristics and the pressure shown on Table II.
- The gas pressure is measured at the initial pressure outlet with the burner on.
- The unit is tested and fitted to operate with natural gas H G20 - 20mbar.
* N.B. Should the supply pressure vary more than +10% of the nominal pressure, it is advisable to install a pressure
regulator ahead of the unit to guarantee the nominal pressure.
- Gas supply connection should be performed by means of metal piping of an appropriate cross section and an approved
shutoff cock should be fitted at source.
- Having connected the gas supply, you should make sure no leaks exist at the joints by checking with bubble soap.
2.3.1

DISCHARGE OF EXHAUST FLUE PRODUCTS VIA A DRAFT HOOD

TYPE "A1" UNIT
The gas unit should be placed beneath a draft hood with its system complying with the Regulations. (This unit needs at least
2cu.m/hr l kW T.C. (Thermal Capacity).
Check kitchen ventilation: it should by complying with the Regulations in force.
2.4

HOW TO ACHIEVE THE NOMINAL THERMAL CAPACITY

Check whether the unit is fitted for the gas type, pressure and category corresponding with the main gas supply.
Indication shown on packing and/or the label of the unit.
If the unit is fitted for another gas type or pressure, you need to first effect a change over to the other gas type.
See Table II for the nozzle, the idle screw (bypass), the primary air regulation, (X mm), the pilot nozzle and the nozzle
pressure for the main burner.
N.B. The names of nozzles "2H" and "3+" are shown on the left side of Table II.
2H= G20 - 20mbar
3+= G30 29mbar and/or G31 - 37mbar coupled gas and pressure. In our sector, we almost always have to deal with G31 -
37mbar!
Table II shows the types of gas and pressure for all burners and respective nozzles, the X mm distance for the adjustment of
primary air (see Fig. 3), the idle screw (bypass), the pilot nozzle, the maximum and minimum pressure at nozzle, the
maximum and minimum thermal capacity, and the gas consumption in l/hr (15°C) or in g/hr in the case of L.P.G.
Attention: If the incoming gas' "dynamic" pressure to the unit is lower than the minimum pressure on Table II, connection
is prohibited; furthermore, the fitter should notify the gas Company that the supply pressure is too low.
N.B. Should the pressure vary more to than +10% of the nominal pressure, e.g. for G20 - 22mbar, it is advisable to mount a
pressure regulator ahead of the unit in order to guarantee the nominal pressure.
Should the supply pressure exceed the maximum pressure on Table II, e.g. for G20 - 25mbar, notify the gas Company.
Make sure the inlet and nozzle pressures agrees with the values shown on Table II.
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GB