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4
A00010
Fig. 5
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3 Phase Monitor Control
Table 2—Phase--Monitor LED Indicators
LED
STATUS
OFF
No call for compressor operation
FLASHING
Reversed phase
ON
Normal
UNIT DAMAGE HAZARD
Failure to follow this caution may result in unit damage.
S
3--phase scroll compressors are rotation sensitive.
S
A flashing LED on phase monitor indicates reverse
rotation. (See Fig. 5 and Table 2.)
S
This will not allow contactor to be energized.
S
Disconnect power to unit and interchange 2 field wiring
leads on unit contactor.
CAUTION
!
COMPRESSOR CRANKCASE HEATER
A crankcase heater is required if refrigerant tubing is longer than
80 ft. (24.38 m).
When equipped with a crankcase heater, energize heater a
minimum of 24 hours before starting unit. To energize heater only,
set thermostat to OFF mode and close electrical disconnect to
outdoor unit.
INSTALL ELECTRICAL ACCESSORIES
Refer to individual instructions packaged with kits or accessories
when installing.
START--UP
UNIT DAMAGE AND/OR PERSONAL INJURY
HAZARD
Failure to follow this caution may result in personal injury
and/or unit component damage.
Service valve gauge ports are equipped with Schrader
valves. Wear safety glasses and gloves when handling
refrigerant.
CAUTION
!
1. Fully open liquid and vapor service valves.
2. Unit is shipped with valve stem(s) front seated (closed) and
caps installed. Replace stem caps after system is opened to
refrigerant flow. Replace caps finger--tight and tighten an
additional 1/12” with wrench.
3. Close electrical disconnects to energize system.
4. Set room thermostat at desired temperature. Be sure set
point is below indoor ambient temperature.
5. Set room thermostat to COOL and fan control to ON or
AUTO mode. Operate unit for 15 minutes. Check system--
refrigerant charge. (See Check Charge.)
PERSONAL INJURY and ENVIRONMENTAL
HAZARD
Failure to relieve system pressure could result in personal
injury and/or death.
1.Relieve pressure and recover all refrigerant before
servicing existing equipment, and before final unit
disposal. Use all service ports and open all flow--control
devices, including solenoid valves.
2.Federal regulations require that you do not vent
refrigerant into the atmosphere. Recover during system
repair or final unit disposal.
!
WARNING
SEQUENCE OF OPERATION
Turn on power to indoor and outdoor units. Transformer is
energized.
On a call for cooling, thermostat makes circuits R--Y and R--G.
Three phase models with scroll compressors, are equipped with a
phase monitor to detect if the incoming power is correctly phased
for compressor operation. (See Fig. 5 and Table 2.) If the phasing is
correct, circuit R--Y energizes contactor, starting outdoor fan motor
and compressor circuit. R--G energizes indoor unit blower relay,
starting indoor blower motor on high speed.
NOTE
: If the phasing is incorrect, the contactor will not be
energized. To correct the phasing, interchange any two of the three
power connections on the field side.
When thermostat is satisfied, its contacts open, de--energizing
contactor and blower relay. Compressor and motors stop.
If indoor unit is equipped with an off delay circuit, the indoor
blower can run an additional 120 sec to increase system efficiency.
CHECK CHARGE
Factory charge amount and desired subcooling are shown on unit
rating plate. Charging method is shown on information plate inside
unit. To properly check or adjust charge, conditions must be
favorable for subcooling charging. Favorable conditions exist
when the outdoor temperature is between 70
_
F and 100
_
F
(21.11
_
C and 37.78
_
C), and the indoor temperature is between
70
_
F and 80
_
F (21.11
_
C and 26.67
_
C). Follow the procedure
below:
Unit is factory charged for 15ft (4.57 m) of lineset. Adjust charge
by adding or removing 0.6 oz/ft of 3/8 liquid line above or below
15ft (4.57 m) respectively.
For standard refrigerant line lengths (80 ft/24.38 m or less), allow
system to operate in cooling mode at least 15 minutes. If conditions
are favorable, check system charge by subcooling method. If any
adjustment is necessary, adjust charge slowly and allow system to
operate for 15 minutes to stabilize before declaring a properly
charged system.
If the indoor temperature is above 80
_
F (26.67
_
C), and the
outdoor temperature is in the favorable range, adjust system charge
by weight based on line length and allow the indoor temperature to
drop to 80
_
F (26.67
_
C) before attempting to check system charge
by subcooling method as described above.
If the indoor temperature is below 70
_
F (21.11
_
C), or the outdoor
temperature is not in the favorable range, adjust charge for line set
length above or below 15ft (4.57 m) only. Charge level should then
be appropriate for the system to achieve rated capacity. The charge