Specifications

7
OPTIONS AND ACCESSORIES
*Factory installed.
†Field installed.
**Cannot be used when unit electrical rating exceeds 80 amps.
††EconoMi$er must be factory installed when used with hinged panels.
ITEM OPTION* ACCESSORY†
Electric Heater and Single Point Kit
X
Integrated Economizer (Durablade)
XX
Integrated Economizer (EconoMi$er)
XX
25% Manual Outdoor Air Damper
XX
50% Manual Outdoor-Air Damper
X
Two-Position Damper (25% Open)
X
Two-Position Damper (100% Open)
X
High-Static Evaporator-Fan Motor and Drive
(Sizes 036-120, Three-Phase Units Only)
X
Perfect Humidity™ Dehumidification Package
X
Convenience Outlet
X
Unit-Mounted Disconnect (Non-Fused)**
X
Hinged Panel Options††
X
Roof Curb (14 in.)
X
Roof Curb (24 in.)
X
Thru-the-Bottom Service Connections
X
Electronic Programmable Thermostat
X
Light Commercial Thermostat
X
Light Commercial Thermidistat
X
Humidistat
X
Fan/Filter Status
X
Thermostat and Subbase
X
Time Guard® II Control Circuit
(3-phase units only)
X
Motormaster® I Low Ambient Control
X
Motormaster IV Low Ambient Control
X
Accusensor™ II Enthalpy Control
X
Accusensor III Differential Enthalpy Sensor
X
Condenser Coil Hail Guard
X
Coil Guard Grille
X
EconoMi$er and Power Exhaust
X
Power Exhaust for EconoMi$er
X
Outdoor-Air Enthalpy Sensor (EconoMi$er)
X
Return-Air Enthalpy Sensor (EconoMi$er)
X
Return-Air Temperature Sensor (EconoMi$er)
X
Indoor-Air Quality CO
2
Sensor (EconoMi$er)
X
LOW AMBIENT CONTROLS
The 551B036-150 standard units are designed to operate at outdoor temperatures down to 25 F.
With accessory Motormaster control (condenser-fan speed modulation) or Motormaster IV con-
trol (condenser-fan cycling), units can operate at outdoor temperatures down to –20 F. The head
pressure controls, which mount in the condenser section, modulate the condenser-fan motor to
maintain correct condensing temperature.
TIME GUARD II CONTROL
Time Guard II Control automatically pre-
vents compressor from restarting for at
least 5 minutes after a shutdown. Field-
installed accessory prevents short cycling
of compressor if thermostat is rapidly
changed. Time Guard II device mounts in
the control compartment of unit.
MOTORMASTER I
MOTORMASTER IV