Lennox Hearth EN03-VDLPM, MN04-VDLPM Pilot Orifice Electronic Appliances Dexen Electronic Valves

Pressure

Regulator

Remove

These

Components

Figure 48

Pilot Stage

Terminal

Ground (TP)

TP

Gas Outlet

To Burner

Pressure-Tap (Inlet)

	IN
TH TP
LO	HI
TH	OUT
	VENT

Pilot Gas

Outlet

PILOT

IN

Supply Gas Inlet

Step 5. 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.

Burner Stage	Regulator	Pressure-Tap
Terminal	Mounting Screw	(Manifold)

Figure 50

Step 6. Refer to Figure 49 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

Orifice

Figure 49

Electronic Appliances

Step 7. Dexen Electronic Valves -

See Figure 50 and the instructions provided with the kit. Remove and discard the two pressure regulator mounting screws. Re- move the pressure regulator and diaphragm. Discard all removed components. Ensure the provided diaphragm is installed properly onto the replacement pressure regulator and install the new pressure regulator using the new screws supplied with the kit. Tighten screws.

See Figure 51 and replace the pilot orifice as follows: Remove pilot hood assembly to access the phillipped pilot orifice. Remove and replace the orifice with the one pro- vided with the kit. Exercise extreme care to prevent damage to or breakage of the ignitor assembly.

ELECTRONIC
Sensor	Pilot
	Hood
Ignitor

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

Figure 51

All Models

Step 8. (Refer to Figure 47 on page 28 )

A. Remove the orifice from the manifold and replace it with the one provided in the kit. See the following table for orifice sizes for natural and propane models. Figure 52 illustrates the orifice.

B. Retrieve the burner and slide the venturi tube over the orifice. Set the shutter adjusting opening as shown in Figure 43, page 25.

Model No.	Orifice size
	Natural	Propane
MPLDV-30	0.070"	#61
		(0.039")
MPLDV-35	#45	0.048"
	(0.082")
MPLDV-40	#41	#54
	(0.046")	(0.055")
MPLDV-45	#40	#53
	(0.098")	(0.595")

Figure 52

Step 9. Reassemble the remaining compo- nents by reversing the procedures outlined in the preceding steps. Use pipe joint compound or Teflon tape on all pipe fittings before install- ing (ensure propane resistant compounds are used in propane applications, do not use pipe joint compounds on flare fittings).

Step 10. Attach the conversion label provided in the conversion kit to the rating plate on the appliance.

Step 11. Turn on gas supply and test for gas leaks.

NOTE: DIAGRAMS & ILLUSTRATIONS NOT TO SCALE.

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