Technical Guide

251933-YTG-V-0913
6 Johnson Controls Unitary Products
• Gas Heat Operation - All single phase models with gas
heat have minimum annual fuel utilization efficiency
(AFUE) of 80%. All three phase models with gas heat
have minimum steady state efficiency of 80%. Each
section includes a durable heat exchanger with
aluminized steel or optional stainless steel tubes, a
redundant gas valve, spark ignition, power venting, an
ignition module for 100% shut-off and all of the safety
controls required to meet the latest ANSI standards.
The gas supply piping can be routed into the heating
compartment through a hole in the base pan of the unit or
through a knockout in the piping panel on the front of the
unit.
Electric Heat Operation - All electric heat models are
wired for a single power source and include a bank of
nickel chromium elements mounted at the discharge of
the supply air blower to provide a high velocity and
uniform distribution of air across the heating elements.
Every element is fully protected against excessive
temperature by thermal limit switches.
The power supply wiring can be routed into the control
box through a threaded pipe connection (field supplied) in
the base pan of the unit or through a knockout in the
wiring panel on the side of the unit.
• Warranty - All models include a 1-year limited warranty
on the complete unit. Compressors and electric heater
elements each carry a 5-year warranty. Aluminized steel
and stainless steel tubular heat exchangers carry a 10-
year warranty.
Factory Installed Options
• Single Input Electronic Enthalpy Economizers -
Includes a slide-in / plug-in damper assembly with fully
modulating spring-return motor actuator capable of
introducing up to 100% outdoor air with nominal 1%
leakage type dampers.
The enthalpy system contains one sensor that monitors
the outdoor air and determines when the air is cool
enough and dry enough to provide free cooling.
The rain hood is painted to match the basic unit and must
be field-assembled before installing.
• Motorized Outdoor Air Intake Damper -Includes a slide-
in / plug-in damper assembly with a 2-position, spring
return motor actuator which opens to a pre-set position
whenever the supply air blower is operating and will drive
fully closed when the blower unit shuts down.
The rain hood is painted to match the basic unit and must
be field assembled before installing.
• Technicoat Condenser Coils - The condenser coils are
coated with a phenolic coating for protection against
corrosion due to harsh environments.
• Technicoat Evaporator Coil - The evaporator coils are
coated with a phenolic coating for protection against
corrosion due to harsh environments.
• ElectroFin® E-coat Condenser Coils - The condenser
coils are coated with an epoxy polymer coating to protect
against corrosion.
• ElectroFin® E-coat Evaporator Coils - The evaporator
coils are coated with an epoxy polymer coating to protect
against corrosion.
• Electric Heaters - Wired for single point power supply.
These nickel chromium heater elements are provided with
limit and automatic reset capability to prevent operation at
excessive temperatures.
• Filter Options - Standard units are shipped with 1" throw-
away filters installed. 2" Pleated Filters, MERV 7 are
offered as a factory installed option.
• Convenience Outlet - This 110 volt outlet can be
“powered” by the unit with a stepdown transformer or the
unit may be ordered with a “non-powered” convenience
outlet that can be wired in the field.
• Disconnect Switch - For gas heat units and cooling units
with electric heat, a HACR breaker sized to the unit is
provided. For cooling only units, a switch sized to the
largest electric heat available for the particular unit is
provided. Factory installed option only.
• Smoke Detectors - (supply air & return air) The smoke
detectors stop operation of the unit by interrupting power
to the control board if smoke is detected within the air
compartment.
• Coil Guard - Customers can purchase a coil guard kit to
protect the condenser coil from damage. This is not a hail
guard kit.
• Stainless Steel Heat Exchanger - For applications in
corrosive environments, this option provides a full
stainless steel heat exchanger assembly.
• Stainless Steel Drain Pan - An optional rustproof
stainless steel drain pan is available to provide years of
trouble-free operation in corrosive environments.
• Bottom Drain Connection - An optional bottom drain
connection is available for inside the curb connections for
applications in cold environments to reduce freezing drain
lines.
• Phase Monitors - Designed to prevent unit damage. The
phase monitor will shut the unit down in an out-of phase
condition.
• Dirty Filter Switch - This kit includes a differential
pressure switch that energizes the fault light on the unit
thermostat, indicating that there is an abnormally high
pressure drop across the filters. Factory installed option or
field installed accessory.
Factory installed smoke detectors in the return air, may
be subjected to freezing temperatures during “off” times
due to out side air infiltration. These smoke detectors
have an operational limit of 32°F to 131°F. Smoke
detectors installed in areas that could be out side those
limitations will have to be moved to prevent having false
alarms.