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PIPING CONNECTIONS
Complete all installation and piping work required for indoor and
outdoor units. If brazing is required pass nitrogen or other inert gas
through piping to prevent formation of cooper oxide. Unit contains R-
22 charge, do not open Schreader valve at this time. Leak test field
piping by pressure method.
PIPING INSULATION
No refrigerant control device is shipped with the unit except 024
model. It is already installed in matching Fan coil units, check
carefully the indoor unit. Insulate suction line adequately (Fig. 8)
COMPLETE ELECTRICAL CONNECTIONS
POWER
– Unit is factory wired for voltage shown on name plate.
Provide adequate fused disconnect switch within sign of unit, readily
accessible, but out of reach children.
Provide for locking switch open (OFF) is advisable to prevent power
from being turned on w hile unit is being serviced.
Route power wires through opening in unit side panel and connect in
unit control box (fig. 9). Unit must be grounded.
CONTROL CIRCUIT WIRING
Refer to wiring diagram for field supplied wiring details.
See Fig. 11 & 12.
Note: - Operation of unit on improper line voltage constitutes
abuse and could affect Carrier Warranty. Do not install
unit in system where voltage may fluctuate above or below
permissible limits.
START-UP
PRELIMINARY CHECKS:
1)
Check that all internal wiring connections are tight and all
barriers, covers and panels are in place.
2)
Field electrical power source must agree with unit name
plate rating.
3)
All service valves must be opened.
START SYTEM
1.
Check that field disconnect is closed.
2.
Set room thermostat to below room temperature, and unit
compressor will start after 3 minutes delay o.
3.
Check back pressure when compressor runs. A dd charge to
keep back pressure at approximately 448kPa (65 PSIG).
REFRIGERANT CHARGING
I M P O R T A N T
For accurate system performance, charge by superheat method
as shown in table 5 and 6.
To check and adjust charge, follow the following procedures:-
1)
Operate unit for a minimum of 15 minutes before checking
charge.
2)
Measure suction pressure by attaching a gauge to suction
line service port.
3)
Measure suction line temperature by attaching a service
thermometer to unit suction line near suction valve.
Insulate thermometer for accurate readings.
4)
Measure outdoor coil air inlet dry-bulb temperature with a
second thermometer.
5)
Measure indoor coil air inlet wet-bulb temperature with a
sling psychrometer.
6)
Refer to table 5. Find air temperature entering outdoor coil
& wet-bulb temperature entering indoor coil. At this
intersection, note the superheat.
7)
Refer to table 6 . Find superheat temperature and suction
pressure, note suction line temperature.
FIG. 8 PIPING INSULATION
CAUTION
THE CONTROL VOLTAGE FROM THE FAN COIL UNIT
MUST BE OF 230V. DO NOT CONNECT THE POWER
SUPPLY TO THE
SIGNAL
FIG. 9 POWER WIRES TO THE SIDE OF UNIT
CAUTION
TO PREVENT PERSONAL INJURY, WEAR SAFETY
GLASSES AND GLOVES WHEN HANDLING
REFRIGERANT. DO NOT OVERCHARGED SYSTEM.
THIS CAN CAUSE COMPRESSOR FLOODING.
NOTE: Model 240 need
to insulate both Suction
and liquid pipes
5