Carrier AQUAZONE 50PSH, Инструкция по установке, запуску и обслуживанию

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• Evaporator freeze protection sensor, mounted between the
thermal expansion device and the evaporator, monitors re -
frigerant temperature between the evaporator coil and ther -
mal expansion valve. If temperature drops below or re -
mains at freeze limit trip for 30 seconds, the controller will
shut down the compressor and enter into a soft lockout
condition. The default freeze limit trip is 26°F. See Fig. 44
and 45.
• The condensate overflow protection sensor is located in
the drain pan of the unit and connected to the ‘COND’ ter -
minal on the UPM board.
Fig. 44 — Waterside Freeze Protection Sensor
Fig. 45 — Air Coil Freeze Protection Sensor
The UPM board includes the following features:
Anti-short Cycle Timer
A 5-minute delay on break timer prevents compressor short
cycling.
Random Start
Each controller has an unique random start delay ranging from
270 to 300 seconds on initial power up to reduce the chance of
multiple units simultaneously starting at the same time after power
up or after a power interruption, thus avoiding creating large in -
rush current.
Low Pressure Bypass Timer
If the compressor is running and the low-pressure switch opens,
the controller will keep the compressor ON for 120 seconds. After
2 minutes if the low-pressure switch remains open, the controllers
will shut down the compressor and enter a soft lockout. The com -
pressor will not be energized until the low-pressure switch closes
and the anti-short cycle time delay expires. If the low-pressure
switch opens 2 to 4 times in 1 hour, the unit will enter a hard lock -
out. In order to exit hard lockout power to the unit would need to
be reset.
Brownout/Surge/Power Interruption Protection
The brownout protection in the UPM board will shut does the
compressor if the incoming power falls below 18 VAC. The com -
pressor will remain OFF until the voltage is above 18 VAC and
ANTI-SHORT CYCLE TIMER (300 seconds) times out. The unit
will not go into a hard lockout.
Malfunction Output
Alarm output is normally open (NO) dry contact. If pulse is select -
ed the alarm output will be pulsed. The fault output will depend on
the DIP switch setting for ALARM. If it is set to CONST, a con -
stant signal will be produced to indicate a fault has occurred and
the unit requires inspection to determine the type of fault. If it is
set to PULSE, a pulse signal is produced and a fault code is detect -
ed by a remote device indicating the fault. The remote device must
have a malfunction detection capability when the UPM board is
set to PULSE.
LED Fault Indicator
The UPM includes an alarm indicator with blink codes to indicate
a UPM fault. See Table 19.
Table 19 — UPM Board Fault Blink Codes
Freeze Protection Sensors 1 and 2 (FP1 and FP2)
FP1 is located on the refrigerant liquid line between the TXV and
the coaxial heat exchanger. If the temperature of the refrigerant en -
tering the coaxial coil (heating mode) drops below or remains at
26°F (–6.6°C) for 30 seconds the UPM controller will shut down
the compressor and enter into a soft lockout condition. Both the
status LED and the Alarm contact will be active. The LED will
flash three (3) times for this alarm condition. If this alarm occurs 2
times (or 4 times if the Lockout DIP switch is set to 4) within an
hour the controller will enter into a hard lockout condition. The
FP1 freeze limit trip can be lowered to 15°F (–9.4°C) by cutting
the R30 sensor located near the top of DIP switch SW1. However,
careful consideration should be given before cutting resistor R30.
For example, if the unit is employing a fresh water system resistor
R30 should remain to protect the coaxial heat exchanger from
freezing and damaging the unit.
FP2 is located on the refrigerant liquid line between the TXV and
the indoor coil. If the temperature of the refrigerant entering the in -
door coil (cooling mode) drops below or remains at 26°F (–6.6°C)
for 30 seconds the UPM controller will shut down the compressor
and enter into a soft lockout condition. Both the status LED and
the Alarm contact will be active. The LED will flash six (6) times
for this alarm condition. If this alarm occurs 2 times (or 4 times if
the Lockout DIP switch is set to 4) within an hour the controller
will enter into a hard lockout condition. The FP2 freeze limit trip
can be lowered to 15°F (–9.4°C) by cutting the R24 sensor located
near the top of DIP switch SW1. However, careful consideration
should be given before cutting resistor R24. For example, a low
refrigerant temperature could cause frosting on the indoor coil,
which restricts airflow causing the unit to malfunction.
Intelligent Reset
If a fault condition is initiated, the 5 minute delay on break time
period is initiated and the unit will restart after these delays expire.
LED
BLINKS
FAULT FAULT CRITERIA
0 None All fault conditions nominal
1 High Pressure
Refrigerant discharge pressure has
exceeded 600 psig
2 Low Pressure
Refrigerant suction pressure has fallen
below 40 psig
3
Water Coil Freeze
Condition
Refrigerant temperature to water coil has
fallen below 26°F for 30s
4
Condensate
Overflow
Condensate levels in unit drain pan are too
high
5 Brown Out Control voltage has fallen below 18 vac
6
Air Coil Freeze
Condition
Refrigerant temperature to the air coil has
fallen below 26°F for 30s