5835254-YIM-A-1119
Johnson Controls Ducted Systems
17
The compressor also uses a polyolester (POE oil), Mobil 3MA
POE. This oil is extremely hygroscopic, meaning it absorbs water
readily. POE oil can absorb 15 times as much water as other oils
designed for HCFC and CFC refrigerants. Take all the necessary
precautions to avoid exposure of the oil to the atmosphere.
POE (polyolester) compressor lubricants are known to cause
long term damage to some synthetic roofing materials.
Procedures that risk oil leakage include, but are not limited to
the following:
• Compressor replacement
• Repairing refrigerant leaks
• Replacing refrigerant components such as the filter drier,
pressure switch, metering device or coil
Units are shipped with compressor mountings that are factory-
adjusted and ready for operation.
Filters
Two-inch filters are supplied with each unit. One-inch filters may
be used with no modification to the filter racks.
Always install filters ahead of evaporator coil. Keep the filters
clean and replace them with filters of the same size and type.
Dirty filters reduce the capacity of the unit and result in frosted
coils or safety shutdown. See the physical data tables for the
number and size of filters needed for the unit.
Do not operate the unit without filters properly installed.
Power and control wiring
Field wiring to the unit, fuses, and disconnects must conform to
provisions of National Electrical Code (NEC), ANSI/NFPA No.
70 – Latest Edition (in U.S.A.), current Canadian Electrical
Code C221, and/or local ordinances. The unit must be
electrically grounded in accordance with NEC and CEC as
specified above and/or local codes.
Voltage tolerances must be maintained at the compressor
terminals during starting and running conditions. The voltage
tolerances are indicated on the unit rating plate and in Table 2.
The internal wiring harnesses furnished with this unit are an
integral part of the design certified unit. Field alteration to
comply with electrical codes is not required.
If any of the wire supplied with the unit must be replaced,
replacement wire must be of the type shown on the wiring
diagram and the same minimum gauge as the replaced wire.
A disconnect must be utilized for these units. Factory installed
disconnects are available.
Note:
Not all local codes allow the installation of a disconnect
on the unit. Confirm compliance with local code before
you install a disconnect on the unit.
Electrical line must be sized properly to carry the load.
Note:
Use copper conductors only.
Each unit must be wired with a separate branch circuit fed
directly from the meter panel and properly fused.
This system uses R-410A refrigerant which operates at
higher pressures than R-22. No other refrigerant may be
used in this system.
Do not leave the system open to the atmosphere. Unit
damage could occur due to moisture being absorbed by
the
POE oil
in the system. This type of oil is highly
susceptible to moisture absorption
Exposure, even if immediately cleaned up, may cause
embrittlement (leading to cracking) to occur in one year
or more. When you perform any service that may risk
exposure of compressor oil to the roof, take precautions
to protect the roofing.
Do not loosen compressor mounting bolts.
Make sure that panel latches are properly positioned on
the unit to maintain an airtight seal.
208/230-3-60 and 380/415-3-50 units control
transformers are factory wired for 230v and 415v power
supply respectively. Change the tap on the transformer
for 208-3-60 or 380-3-50 operation. See the unit wiring
diagram.
Avoid damage to internal components if you drill holes to
install a disconnect.
