Middleby Marshall Oven owner manual VIII. Preparation for Various Gases, For USE with Natural GAS

SECTION 2

INSTALLATION

VIII. PREPARATION FOR VARIOUS GASES

Before proceeding to set up the oven for a specific gas, the main gas supply valve and the electrical supply circuit breaker should be turned off.

When preparing the oven for use of Group H or L Natural gases, the orifice (Manifold) pressure should be adjusted to the values shown in the chart on Page 1-1.

The main orifice and also the by-pass (low flame) orifice should be changed for the specific gas type used as shown in the following Table, also refer to Section IX, CHANGING ORIFICES.

FOR USE WITH NATURAL GAS

The input to the burner can be determined using the orifice (manifold) pressure data or by the volume supplied using the gas meter.

Using the orifice pressure data you must know the specific gas quality used and when using the volume method you must know the heat value (HuB) of the gas used (Obtainable from your local gas supplier).

If you used the orifice pressure method, you should double check the rated input using the volume method.

If the measured input does not correspond with the rated input, check first that correct orifices are installed. If the orifice sizes are as specified, check and correct the supply and orifice pressures to obtain the correct input based on the gas meter reading.

FOR USE WITH LIQUID (LP) GAS

When using liquid gas the converter in the multifunction gas valve has to be turned end over end - 180° (Refer to Figure 2- 36). This takes the governor out of operation.

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