SECTION 2
INSTALLATION
4.Replace cover screw on adjustment valve and turn off main gas supply valve.
5.Record the reading obtained from the gas meter and calculate obtained gas flow. Compare this to the indicated flow in the CHART OF ORIFICE SIZES, GAS PRESSURES, NOMINAL INPUT RATINGS AND GAS FLOW on Page 1.
6.Note the following comments and procedures to assure correct gas supply pressure and adjusting the gas valve to obtain proper orifice (manifold) pressure.
XI. VARIATIONS OF RATED SUPPLY
PRESSURES
Special attention should be given to the supply pressure and gas flow pressure at the supply connection to the oven. The nominal supply pressure for gas family Group 2 (natural gas) should be 20 mbar.
If the supply pressure is lower or higher than the rated (nominal) pressure then the reason should be investigated and the gas supplier contacted.
If the supply pressure is lower than 17 mbar’s or higher than 25 mbar’s then the oven should be shut down and the gas supplier notified. No adjustment of the oven controls should be made and the oven should not be operated.
TO CHECK GAS SUPPLY PRESSURE:
1.Close main gas supply valve.
2.Remove supply (inlet) pressure measuring stud screw from gas valve and attach the manometer to the stud.
3.Open main gas supply valve and restart oven with temperature control at maximum setting.
4.Measure inlet (supply) pressure. For all natural gases this should be between 17 and 25 mbar’s.
5.Turn oven off, close main gas supply valve, remove manometer from stud and tighten cover screw in to pressure measuring stud.
ORIFICE (MANIFOLD) PRESSURE METHOD:
1.Turn off main gas supply valve.
2.Remove pressure measuring stud screw located at the
3.Remove cover screw from the gas valve pressure (governor) adjustment valve.
4.Open main gas supply valve and start oven according to supplied instructions with the temperature control at maximum setting.
5.Once oven is in operation, adjust pressure valve (governor) to the orifice pressure value as shown for the specific gas in the Gas Specifications Table.
6.Turn oven off, close main gas supply valve, remove “U” tube manometer and tighten cover screw into pressure measuring stud.