Williams 2903512 - Manual (Page 9)

Gas Conversions
Converting to another gas type must be performed by a qualified service technician. If the type of the gas supplied to the
dwelling is not the same type as your furnace (natural or LPG gas), it must be converted.
It will be necessary to do the following:
1. Change nozzle.
a. Remove the screw indicated
to the right.
2. Without removing anything else, remove the nozzle from the burner inserting the screwdriver as indicated by the arrow.
Nozzle
3. Change the nozzle, attach the screw indicated at point 1 and set the burner pressure as indicated in the table below:
Gas Type Nozzle Part Number Nozzle Diameter
ressure at the correct value
Natural Gas JGLL069 0.1 in.
LP Gas JGLL062 0.06 in.
Minimum Inlet Line Gas
Pressure
Maximum Minimum
Gas Type
Manifold Gas Pressure Manifold Gas Pressure
Natural Gas 7.0-inches w.c. 3.2-inches w.c. 1.8-inches w.c.
LP Gas 11.0-inches w.c. 10.6-inches w.c. 6.5-inches w.c.
4. Check the gas pressure and settings.
Minimum Burner Pressure Setting:
1. Set LOW burner capacity by pressing button Z2
2. Connect a micro manometer to the test gauge B (Figure 8)
3. Rotate the internal screw “D” (Figure 8) and set the pressure at the correct value
Maximum Burner Pressure Setting:
1. Set HI burner capacity by pressing button Z2
2. Connect a micro manometer to the test gauge B (Figure 8)
3. Rotate the external screw “C” (Figure 8) and set the p
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