Lennox LGH036-072S User manual

Page 1
INSTALLATION INSTRUCTIONS FOR LP KIT USED ON
LGH/KG/KD/ZG 024-090 PACKAGED ROOFTOP UNITS
Litho U.S.A.
507586-01
8/2016
Supersedes 1/2016
©2016
NATURAL TO LP (PROPANE)
GAS CHANGEOVER KIT
PACKAGED UNITS KITS
AND ACCESSORIES
WARNING
This conversion kit shall be installed by a quali
fied service agency in accordance with the
manufacturer's instructions and all applicable
codes and requirements of the authority having
jurisdiction. If the information in these instruc
tions is not followed exactly, a fire, an explosion
or production of carbon monoxide may result
causing property damage, personal injury or
loss of life. The qualified service agency is re
sponsible for the proper installation of this kit.
The installation is not proper and complete un
til the operation of the converted appliance is
checked as specified in the manufacturer's in
structions supplied with the kit.
Shipping and Packing List
Package 1 of 1 contains:
7- Orifices (3 in 21A01)
1- Spring kit (2 in 14N21 & 21A02)
1- Bag assembly containing:
3-Conversion plates (1 in 21A02)
1-Conversion sticker
1-Acrylic sheet
1-J/P19 harness (14N21 & 21A01 only)
Requirements
This conversion kit shall be installed by a qualified service
agency. A qualified service agency is any individual, firm,
corporation or company which either in person or through
a representative is engaged in and is responsible for the
connection, installation, repair or servicing of gas
utilization equipment or accessories, who is experienced
in such work, familiar with all precautions required, and
has complied with all the requirements of the authority
having jurisdiction.
Canadian installations only - The conversion shall be
carried out in accordance with the requirements of the
Provincial authorities having jurisdiction and in
accordance with the requirements of the
CAN/CGA-B149.1 and .2 Installation Code.
Application
The LP/propane gas changeover kit is required for gas
conversion as shown in table 1. The 10th character on the
unit nameplate determines the type of gas valve. For
example, ZGA060S4BH1G would contain a two-stage,
high heat gas valve.
Installation
WARNING
Improper installation, adjustment, alteration, ser
vice or maintenance can cause property damage,
personal injury or loss of life. Installation and ser
vice must be performed by a licensed professional
HVAC installer or equivalent, service agency, or the
gas supplier
1- Turn main manual shut-off valve off and turn off
electrical supply to unit. Set thermostat to “Off”
position.
2- Open access panels as shown in figure 1. On
LGH/KG/KD units, remove the mullion between the
heat and compressors sections.
TABLE 1
Unit Cat. No. Part No. Htg. Stages 10th Character
LGH036-072S, KG 024-090, KD 024-030H, ZG 036-072 14N20 614839-01 Single-Stage S, M, T, W, Y, Z
LGH036-072S, KG 024-090, KD 036-060H, ZG 036-072 14N21 614839-02 Two-Stage Med. & High H, U, Q, X
LGH036-072H, LGH036-074U, KG 036-074, KD 036-060H 21A01 614839-03 Two-Stage Standard B
LGH048-074U, LGH060H 21A02 614839-04 Four-Stage High D

Page 2
FIGURE 1
ZG 036-060 UNITS
REMOVE
PANELS
REMOVE
HEAT CONTROL
ACCESS PANEL
CAUTION
Danger of sharp metallic edges. Can cause injury.
Take care and wear protective clothing when
servicing unit to avoid accidental contact with
sharp edges.
IMPORTANT-The gas supply shall be shut off prior to
disconnecting the electrical power, before proceeding
with this conversion.
3- Remove and retain four screws securing manifold to
burner box; remove manifold. See figure 2, 3, or 4.
4- Remove orifices from manifold and install the orifices
provided in kit. Unit will have 3, 5, or 7 burners.
Replace only the orifices which have a burner
installed.
On four-stage units only, the two left orifices are
0.050”: and the right five orifices are 0.052”. See
figure 4 for proper orifice placement.
CAUTION - Tighten orifices with pipe threads to 6.25
ft.lbs. Do not overtighten.
IMPORTANT - Do not use thread compound on gas orifices.
5- Replace the manifold and secure with retained
screws.
6- Install spring kit as shown in figure 5 for
single-stage gas valves, figure 6 for two-stage and
four-stage White Rodgers gas valves, and figure 7
for two-stage Honeywell gas valves. Also refer to
the manufacturer's instructions provided with
spring kit. When installing 14N21 kit, discard the
unused spring kit.
FIGURE 2
BURNER BOX ASSEMBLY - ZG 036-060
ORIFICES
(3, 5, OR 7)
Remove and retain two
screws on each side;
remove manifold.
GAS
VALVE
GAS
MANIFOLD
BURNERS

Page 3
FIGURE 3
BURNER BOX ASSEMBLY - LGH/KG/KD 024-090
GAS VALVE
GAS
MANIFOLD
ORIFICES
(3, 5, OR 7)
Remove and retain two
screws on each side;
remove manifold.
Remove and retain two
screws on each side;
remove manifold.
GAS VALVE
GV3
FIGURE 4
BURNER BOX ASSEMBLY - LGH 036, 048, 060, 072U - FOUR-STAGE HEAT
GAS
MANIFOLD
ORIFICES
(0.050)
Remove and retain two
screws on each side;
remove manifold.
Remove and retain two
screws on each side;
remove manifold.
ORIFICES
(0.052)
GAS VALVE
GV1
Note - Ignitors and sensors
for all capacities are shown.

Page 4
1.
2.
3.
4.
5.
6.
INLET
PRESSURE
TAP
Remove regulator cap screw and pressure regulator
adjusting screw.
Remove existing spring.
Insert replacement spring.
Install the new plastic pressure regulator adjustment
screw so that the top of the screw is flush (level) with
the top of the regulator. Turn the pressure regulator
adjusting screw clockwise six complete turns, This
adjustment provides a preliminary pressure setting of
about 10.5” w.c. (2.6 kPa) for the LP regulator.
Check regulator setting either with a manometer or by
clocking the gas meter.
Reinstall cap screw.
CONVERTING SINGLE-STAGE GAS VALVE
(Natural to LP)
FIGURE 5
CAP SCREW
PRESSURE REGULATOR
ADJUSTING SCREW
(White)
SPRING
(Red)
GAS INLET
CONVERTING TWO- & FOUR-STG. GAS VALVES
(White Rodgers Natural to LP/Propane)
FIGURE 6
High Low
1- Remove both high fire and low fire springs from the gas valve.
2- Replace both high fire and low fire springs with the provided LP
springs color-coded white.
3- Install the high fire adjustment screw and adjust approximately
12 turns.
4- Install the low fire adjustment screw and adjust approximately
8 turns.
5- Install both regulator screw covers.
REGULATOR
COVER SCREW
PLASTIC REGULATOR
ADJUSTMENT SCREW
REGULATOR SPRING
1. Turn off the gas supply to the unit.
2. Remove the pressure regulator cover assembly. See the gas
valve illustration below.
3. Remove the existing stem/spring assembly.
4. Insert the replacement stem/spring assembly.
5. Replace the pressure regulator cover assembly and tighten the
screws.
6. Apply the conversion label to the gas control.
CONVERTING TWO-STAGE GAS VALVE
(Honeywell Natural to LP/Propane)
PRESSURE
REGULATOR
COVER ASSEMBLY
STEM
(SPRING ASSEMBLY,
LP - BLACK)
FIGURE 7

Page 5
Install J/P19 Jumper Harness
Two Stage Gas Valves Only
1- Locate J19/P19 combustion air blower connectors in
divider panel between heat and compressor
sections.
2- Disconnect J19/P19.
3- Install kit harness between disconnected plugs. See
figure 8.
FIGURE 8
INSTALL JUMPER PLUG
COMBUSTION
AIR BLOWER
P19 J19
COMBUSTION
AIR BLOWER
P19 J19 J21 P21
2-Install kit harness.
1-Disconnect
P19/J19.
DIVISION
PANEL
B6
HEAT SECTION COMPRESSOR
SECTION
B6

Page 6
Start-Up And Adjustments
1- Replace heat section access panels and mullion.
2- Close heat section access panel.
A-To place unit in operation:
1- Turn main manual shut-off valve on.
WARNING
Danger of explosion. Can cause injury
or death. Do not attempt to light
manually. Unit has a direct spark
ignition system.
2- Wait five minutes, then open manual knob on gas
valve and replace compressor access panel.
3- Restore electrical supply to unit and set fan switch to
“Auto” or “On.” Move system selection switch to
“Heat” and adjust thermostat setting above room
temperature.
4- The combustion air blower will start and burners will
light within 40 seconds.
5- If burners do not light first time (gas line not fully
purged), ignition system will attempt to light two more
times before locking out gas valve operation.
6- If lockout occurs, repeat steps 1, 2 and 3 above.
B-To shut down unit operation:
1- Set thermostat selection switch to “Off” position,
remove heat control access panel and turn manual
knob on gas valve to “Off” position.
2- Replace heat control access panel.
C-Heating Adjustment
Check gas line pressure with unit firing at maximum rate.
A minimum of 10.8” w.c., and a maximum of 13.5” w.c.
should be maintained. Manifold pressure is preset as
shown on the appropriate conversion label provided in
this kit.
No adjustment should be necessary. On multiple unit
installations, each unit should be checked in sequence
beginning with the one closest to the supply gas main and
progressing to the one furthest from the main.
Identifying Unit As LP Converted
1- Locate 580207-04, -05, and -06 conversion plate
labels provided in kit. Select the appropriate label and
discard the other two labels.
Note - 21A02 kits have one conversion plate; there are no
further labels to discard.
2- Make a check mark in the appropriate box on the
conversion plate corresponding to unit model number
shown on nameplate. Affix appropriate conversion
plate near unit nameplate.
3- Complete installer information on converter sticker
and affix to vestibule panel. Affix acrylic sheet over
converter sticker.