5012886-YIM-B-0517
8
Johnson Controls Unitary Products
Power Wiring
Check the available power and the unit nameplate for correct
voltage. Run the necessary number of properly sized wires to
the unit. Provide a disconnect switch (if not included with the
unit) and fusing as required. Route the conduit through the
large knockout located on the front of the electrical box. See
Table 5 for Electrical Data.
The disconnect switch may be bolted to the side of the unit but
not to any of the removable panels; this would interfere with
access to the unit. Make sure that no refrigerant lines will be
punctured when mounting the disconnect switch, and note that
it must be suitable for outdoor installation.
Control Wiring
Route the necessary low voltage control wires from the Smart
Equipment™ control board to the thermostat and also from the
low voltage condenser unit control box to the terminal block
inside the evaporator unit. Refer to Figures 3 thru 5 for field
wiring diagrams.
Compressors
The scroll compressors used in this product are specifically
designed to operate with R-410A Refrigerant and cannot be
interchanged.
The compressor also uses a polyolester (POE oil), Mobil 3MA
POE. This oil is extremely hydroscopic, 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
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 which risk oil leakage include, but are not limited to,
compressor replacement, repairing refrigerant leaks, replacing
refrigerant components such as filter drier, pressure switch,
metering device or coil.
Units are shipped with compressor mountings which are factory
adjusted and ready for operation.
Compressor Crankcase Heaters
The compressors are equipped with crankcase heaters to
prevent the migration of refrigerant to the compressors. The
heaters are energized only when the unit is not running.
If the main switch is disconnected for long periods of shut down,
do not attempt to start the unit for 8 hours after the switch has
been re-connected. This will allow sufficient time for all liquid
refrigerant to be driven out of the compressor.
Phasing
Three-phase, scroll compressors operate in only one direction.
If the scroll is drawing low amperage, has similar suction and
discharge pressures, or is producing a high noise level, the
scroll is misphased. Change the incoming line connection
phasing to obtain the proper rotation.
All power and control wiring must be in accordance with
National and Local electrical codes.
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 performing any service that may risk
exposure of compressor oil to the roof, take precautions
to protect roofing.
Do not loosen compressor mounting bolts.
Scroll compressors require proper rotation to operate
properly. Failure to check and correct rotation may result
in property damage.
