Technical Guide

5126749-YTG-A-0715
2 Johnson Controls Unitary Products
• Full Perimeter Base Rails - The easily removable base rails
provide a solid foundation for the entire unit and protects the
unit during shipment. The rails provide fork lift access from all
sides, and rigging holes are also provided so that an over-
head crane can be used to place the units on a roof. On
applications where the unit is placed on a pad, the base will
keep the unit off the pad to deter corrosion. On applications
where height is limited, the base rails may be removed by
removing 2 screws in each corner.
• Attractive Appearance - A single-piece top cover containing
a top-discharge condenser fan arrangement requires less
square footage on installation and provides a wider variety of
installations. The one-piece design adds greater water integ-
rity. Rounded corners with water drip edges add to the attrac-
tive appearance.
• Top Discharge - The top-discharge outdoor fan does not
disrupt neighboring areas or dry out vegetation surrounding
the unit. The warm air from the top mounted fan is blown up
and away from the structure and any landscaping.
• Outdoor Coil Grille - All models utilize a stamped slotted
design which provides superior impact protection against
small objects during transit and after installation.
• Low Operating Sound Level - The upward air flow carries
the normal operating noise up and away from the living area.
The rigid top panel effectively isolates noise. Isolator
mounted compressor and the rippled fins of the outdoor coil
muffle the normal fan motor and compressor operating
sounds. The unique formed base pan also aids in sound
attenuation with its structural design.
• Fan System - All models operate over a wide range of
design conditions with a standard ECM indoor fan motor.
These units easily match all types of applications and pro-
vide greater on-site flexibility to match comfort requirements.
The cooling speed is factory-set and can be field-adjusted to
a second speed. The heating speed is factory set to maintain
mid point rise at the units heating input, but can be field
adjusted. This allows maximum comfort conditions.
• Simple Control Circuit - Field thermostat wiring connects to
color coded leads using twist on wire connections. Cooling
controls use contactor and relays for simple application and
troubleshooting. Mate-n-lock plug connectors are used. The
electrical control box is not located in the compressor com-
partment. The controls are mounted to allow the separate
access panel to be removed for trouble shooting and mainte-
nance without affecting the normal system operating pres-
sures. All wiring internal to the unit is color/number coded.
• Protected Compressor - The compressor is internally pro-
tected against high pressure and temperature. This is
accomplished by the simultaneous operation of high pres-
sure relief valve and a temperature sensor which protect the
compressor if undesirable operating conditions occur.
• Pressure Switches - A high pressure switch is standard in
all units. It is an automatic reset switch. When discharge
pressure reaches 650 psi, the compressor will de-energize
until pressure reaches 450 psi.
• Exclusive Coil Design - Grooved copper tubes and
enhanced aluminum fin construction improves heat transfer
for maximum efficiency and durability for long-lasting durabil-
ity and efficient operation. Indoor coils will use tin-coated
copper tubing with aluminum fins for effective heat transfer.
• Electric Heat - All electric heat models use 6HK electric
heat, which are available in 230v/1/60 from 2 kW to 25 kW,
230v/3/60 10kW to 25kW, and 460v/3/60 10kW to 25kW.
Most kits stageable above 10 kW. Single phase single point
field wiring kits are available for all applications except 25kW.
• Low Maintenance - Long life, permanently lubricated con-
denser and evaporator fan motor bearings need no annual
maintenance, adding greater reliability to the unit. Slide-out
blower assembly and evaporator coil assembly can be easily
removed for cleaning.
• Easy Service Access - Individual access panels are pro-
vided in access to all major components - compressors,
evaporator coils, blower, controls/electric heat kits, filters,
etc. that makes servicing easy. Removing these panels allow
easy removal of the components such as the blower assem-
bly for maintenance and ease of troubleshooting.
• Replacement Parts - T
he installer requires no special train-
ing to replace any of the components of these units and the
number of new components have been reduced to minimize
the inventory of unique parts.