Lennox Hearth MPD-35 Series Millivolt Honeywell Systems, Kits, Models, Unit Type, Adjusting Knob

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Millivolt Honeywell Systems -

Natural To Propane Gas Conversion

Kits

Models	Unit Type	Catalog No.
MPDT-3328	Millivolt	26M51
MPDR-3328
MPD-3530	Millivolt	26M52
MPD-4035	Millivolt	26M53
MPD-4540	Millivolt	26M54
MPDT-3328	Electronic	26M59
MPDR-3328
MPD-3530	Electronic	26M60
MPD-4035	Electronic	26M61
MPD-4540	Electronic	26M62

Millivolt SIT Systems -

Natural To Propane Gas Conversion

Kits

Models	Unit Type	Catalog No.
MPDT-3328	millivolt	H2009
MPDR-3328
MPD-3530	millivolt	H2011
MPD-4035	millivolt	H2013
MPD-4540	millivolt	H2015

Step 4. Millivolt Appliances - SIT Systems

a. See Figure 59 and the instructions provided with the kit. Using a Torx T20, remove and discard the three pressure regulator mounting screws. Remove the pressure regulator, spring, poppet, diaphragm and bushing. Discard all removed components. Ensure the rubber gas- ket installed on the back of the replacement pressure regulator is properly positioned and install the new pressure regulator using the new screws supplied with the kit. Tighten screws to 25 In. lb. torque.

Millivolt Honeywell Systems -

Propane To Natural Gas Conversion

Kits

Models	Unit Type	Catalog No.
MPDT-3328	Millivolt	26M55
MPDR-3328
MPD-3530	Millivolt	26M56
MPD-4035	Millivolt	26M57
MPD-4540	Millivolt	26M58
MPDT-3328	Electronic	26M63
MPDR-3328
MPD-3530	Electronic	26M64
MPD-4035	Electronic	26M65
MPD-4540	Electronic	26M66

Millivolt SIT Systems -

Propane To Natural Gas Conversion

Kits

Models	Unit Type	Catalog No.
MPDT-3328	millivolt	H2010
MPDR-3328
MPD-3530	millivolt	H2012
MPD-4035	millivolt	H2014
MPD-4540	millivolt	H2016

SIT Millivolt Gas Valve

Pressure

Regulator

Remove

These

Components

Figure 59

NOTE: DIAGRAMS & ILLUSTRATIONS NOT TO SCALE.

Pilot for SIT Millivolt Gas Valve

Pilot

Orifice

Figure 60

b. Attach manometer to the manifold side pressure test fitting and verify manifold pres- sure 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 60 and remove the pilot hood assembly to access the hexed pilot ori- fice. Remove and replace the orifice with the one provided with the kit.

Step 5. Millivolt Appliances -

Honeywell Systems

a. Convert the gas valve as follows (see Figure 61 ):

Remove the plastic protecting cap. Remove the gas type setting screw by turning it coun- terclockwise. Obtain the replacement gas type setting screw from the kit and screw it into place (red for propane and blue for natural gas). Tighten the gas type setting screw by turning it clockwise. Replace the plastic pro- tecting cap.

Honeywell Millivolt Gas Valve

Adjusting Knob

Regulator Cap

Conversion screw

(blue natural gas;

red LP/propane gas)

Figure 61