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INSTALLATION INSTRUCTIONS FOR LOW AMBIENT CONTROL KIT LB-57113BM (27J00)
USED WITH SINGLE-COMPRESSOR HEAT PUMP UNITS
Litho U.S.A.
502,818M
11/98
Supersedes 3/96
®
E
1998 Lennox Industries Inc.
Dallas, Texas
LOW AMBIENT CONTROL KIT
KITS COMMON TO HEATING
AND COOLING EQUIPMENT
INSTALLATION INSTRUCTIONS
SHIPPING AND PACKING LIST
Package 1 of 1 contains:
1- Low ambient pressure switch assembly (S11)
1- 36" (914 mm) length of 1/4" (6.35 mm) copper tube
with flare nuts
1- Relay
1- 20ĆFoot length of wire
4- 20" Lengths of wire
1- Bag assembly each containing:
8-Wire nuts
2-Saddle valves
4-#10-16 X 5/8" S.D.S.T. screws
1-Schrader depressor tee with seal cap
APPLICATION
The low ambient pressure switch (S11) cycles the
outdoor fan while allowing compressor operation in the
cooling cycle. This intermittent fan operation results in
a high evaporating temperature which allows the
system to operate without icing the evaporator coil and
losing capacity. This kit is designed for use in ambient
temperatures no lower than 30°F.
Lennox recommends a belly-band style crankcase heater
(P-8-8852, 240v, 45w) be added to compressors which
do not have one. A freezestat (LB-62858CA) should also
be added to any system using a low ambient kit.
NOTE - Do not use this low ambient kit on units with
capillary tube metering devices. Install an expansion
valve metering device if using this kit.
INSTALLATION
A-Pressure Switch Assembly
1- Disconnect power to unit.
2- Remove compressor compartment access panel.
3- Install valve depressor tee discharge line gauge port.
4- Install pressure switch in compressor compartment
with screws provided. Switch should be installed in a
vertical position higher than mid-point of compressor.
See figure 1.
FIGURE 1
TYPICAL INSTALLATION
S11 LOW AMBIENT
PRESSURE SWITCH
HIGH
PRESSURE
SWITCH
COMPRESSOR
DISCHARGE
LINE
S24 LOSS
OF CHARGE
SWITCH
VALVE
DEPRESSOR
TEE
SHOCK
LOOP
5- Connect copper line to low ambient pressure
switch and open side of depressor tee (provided).
Provide a shock loop in copper tubing to prevent
breakage from vibration. Tighten connections.
Depressor tee port with valve core is used as
service port. If necessary, valve core can be moved
to other leg of tee.
