b. Attach manometer to the manifold side pressure test fitting and verify manifold pressure reads 3.5 inches water column (0.87 kPa) for natural gas, and 10.0 inches water column (2.49 kPa) for propane gas.

c. Refer to Figure 40 and remove the pilot hood assembly to access the hexed pilot orifice. Remove and replace the orifice with the one provided with the kit.

Pilot Hood Pilot for SIT MillivoltGas Valve

Pilot

Orifice

Figure 40

Step 5. Electronic Appliances -Honeywell Systems

See Figure 41 and the instructions provided with the kit. Remove the slotted cap screw, o-ring, pressure-regulating adjusting screw and spring. Retain all parts for possible later use. Install new components from the kit. Black cap and red spring for propane gas units. Silver cap and stainless steel spring for natural gas units.

Before installing the cap, attach manometer to the manifold side pressure test fitting and adjust screw until pressure reads 3.5 inches water column (0.87 kPa) for natural gas, and 10.0 inches water column (2.49 kPa) for propane gas.

CONTROL

OFF ON

Inlet Pressure Test Port

 

 

I

EITNIG

 

 

 

 

IPS

Manifold

Pressure

Test Port

Slotted

Cap

Spring

Adjusting

Screw

Figure 41

See Figure 42 and replace the pilot orifice as fol- lows: Remove the igniter assembly retainer clip, and carefully remove the igniter assembly.

Exercise extreme care to prevent damage to or breakage of the igniter assembly. Remove the screw securing the pilot assembly to its mounting bracket. Back off the flare nut at the end of the pilot gas line to free the pilot assembly from the gas line. Remove the pilot orifice and replace it with the one provided with the conversion kit. Reinstall the pilot assembly by reversing the steps detailed here.

When reinstalling the igniter assembly, use extreme care to prevent damage and break- age. Do not apply any leverage to the igniter assembly while restoring the retainer clip to its original position.

Pilot Assembly

Pilot Orifice

Igniter Assembly

Flare Nut

Retaining Clip

Note: If the Igniter is damaged, a replacement kit is available - order Catalog Number 87L54.

Figure 42

All Models

Step 6. Remove the orifice from the manifold and replace it with the one provided with the kit. See Table 7 for orifice sizes for natural and propane models. Figure 43 illustrates the orifice.

Burner Orifice Sizes

Elevation 0-4500 feet ( 0-1372 meters)

Models

Natural

Propane

Gas

Gas

 

 

drill size (inches)

drill size (inches)

 

 

 

MPB-3328

#47 (.0785")

#1.2mm (.048")

 

 

 

MPB-3530

#44 (.086")

#55 (.052")

 

 

 

MPB-4035

#37 (.104")

1/16" (.0625")

 

 

 

MPB-4540

#36 (.1065")

#52 (.0635")

 

 

 

Table 7

Figure 43

Step 7. Reassemble all removed components by reversing the procedures outlined in the preceding steps. Use pipe joint compound or Teflon tape on all pipe fittings before installing (ensure propane resistant compounds are used in propane applications, do not use pipe joint compounds on flare fittings).

Step 9. Attach the conversion label provided in the conversion kit to the rating plate on the appliance.

Step 10. Turn on gas supply and test for gas leaks.

NOTE: DIAGRAMS & ILLUSTRATIONS NOT TO SCALE.

The manufacturer reserves the right to make changes at any time, without notice, in design, materials, specifications, prices and also to discontinue colors, styles and products. Consult your local distributor for fireplace code information.

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20 P/N 850,033M REV. B 05/2006

1110 West Taft Avenue • Orange, CA 92865