Instruction manual

6
Start--Up
CAUTION
!
UNIT OPERATION AND SAFETY HAZARD
Failure to follow this caution may result in minor personal
injury, equipment damage or improper operation.
To prevent compressor damage or personal injury, observe the
following:
S Do not overcharge system with refrigerant.
S Do not operate unit in a vacuum or at negative pressure.
S Do not disable low pressure switch in scroll compressor
applications.
S Dome temperatures may be hot.
CAUTION
!
PERSONAL INJURY HAZARD
Failure to follow this caution may result in personal
injury.
Wear safety glasses, protective clothing, and gloves when
handling refrigerant and observe the following:
S Front seating service valves are equipped with Schrader
valves.
CAUTION
!
ENVIRONMENTAL HAZARD
Failure to follow this caution may result in environmental
damage.
Federal regulations require that you do not vent refrigerant
to the atmosphere. Recover during system repair or final
unit disposal.
Follow these steps to properly start up the system:
1. After system is evacuated, fully open liquid and vapor
service valves.
2. Unit is shipped with valve stem(s) front seated (closed) and
caps installed. Open fully by turning the stem counter
clockwise as far as it will go, and tighten lightly. This opens
the valve to refrigerant flow, and closes the gage port. To
leave gage port open, fully open the valve, and then turn the
stem clockwise a few turns. This will allow pressure to be
sensed without restricting refrigerant flow.
Replace stem caps after system is opened to refrigerant flow.
Replace caps finger--tight and tighten with wrench an
additional 1/12 turn
NOTE: The gage port does not contain a Schrader core.
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, as desired. Operate unit for 15 minutes.
Check system refrigerant charge.
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
level could then be checked at another time when the both indoor
and outdoor temperatures are in a more favorable range.
NOTE: If line length is beyond 80 ft (24.38 m) or greater than
20 ft (6.10 m) vertical separation, See Long Line Guideline for
special charging requirements.
Major Components
Control Board
The AC control board controls the following functions:
S Compresso r contactor operation
S Outdoor fan motor operation
S Compressor external protection
S Pressure switch monitoring
S Time Delays
Field Connections
When used with a standard thermostat, it is recommended to use 3
thermostat control wires to be connected to R, Y and C. When
using 3 wires, all diagnostic and time delay features are enabled
(See Fig. 12).
When o nly 2 thermostat control wires are available, un its
beginning with serial numbers 3006E and newer will function, but
some control features are lost. (See Fig. 13). With only 2 wires
connected, the circuit board will be powered down whenever there
is no call for cooling, and the following will result:
S Compressor time delay is reduced from 5 minutes to 10 seconds
S When the thermostat is not calling for cooling, the amber status
light will be off, and no diagnostics codes will be available
S All system counters will be reset on each new call for cooling
When using Infinity Communicating control, 4 wires are required
to be connected to the ABCD terminal (see Fig. 11)
Compressor Internal Relief
The compressor is protected by an internal pressure relief (IPR)
which relieves discharge gas into the compressor shell when
differential b etween suctio n an d d isch arge pressu re exceed s
550-- 625 psi. The compressor is also protected by an internal
overload attached to motor windings.
24APA