Carrier Aquazone 50PSW025, Installation, Start-Up And Service Instructions Manual

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power up or after a power interruption), thus avoiding creating a
large electrical spike.
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
compressor will not be energized until the low-pressure switch
closes and the anti-short cycle time delay expires. If the
low-pressure switch opens 2-4 times in 1 hour, the unit will enter a
hard lockout. To exit the 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 down the
compressor if the incoming power falls below 18 VAC. The
compressor 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
selected 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 constant 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 detected by a remote device indicating the fault. See
L.E.D Fault Indication table in the trouble shooting section of this
document for blink codes. The remote device must have a
malfunction detection capability when the UPM board is set to
"PULSE".
NOTE: If 24 VAC output is needed R must be wired to
ALR-COM terminal; 24 VAC will be available to the ALR-OUT
terminal when the unit is in the alarm condition.
Test Dip Switch
A test dip switch is provided to reduce all time delay settings to
10 seconds during troubleshooting or verification of unit
operation.
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.
During this period, the fault LED will indicate the cause of the
fault. If the fault condition still exists or occurs 2 or 4 times
(depending on 2 or 4 setting for Lockout dip switch) before
60 minutes, the unit will go into a hard lockout and requires a
manual lockout reset.
Lockout Reset
A hard lockout can be reset by turning the unit thermostat off and
then back on when the "RESET" dip switch is set to "Y" or by
shutting off unit power at the circuit breaker when the "RESET"
dip switch is set to "R".
CONSIDERATIONS
1. Always check incoming line voltage power supply and
secondary control voltage for adequacy. Transformer
primaries are dual tapped for 208 and 230 volts. Connect the
appropriate tap to ensure a minimum of 18 volts secondary
control voltage. 24 volts is ideal for best operation.
2. Long length thermostat and control wiring leads may create
voltage drop. Increasing wire gauge or up-size transformers
may be required to ensure minimum secondary voltage
supply.
3. Carrier recommends the following guidelines for wiring
between a thermostat and the unit: 18 GA up to 60 ft, 16 GA
up to 100 ft and 14 GA up to 140 ft.
4. Do not apply additional control devices to the control circuit
power supply without consulting the factory. Doing so may
void equipment warranties.
5. Check with all code authorities on requirements involving
condensate disposal/over flow protection criteria.
START-UP
Use the procedure outlined below to initiate proper unit start-up.
NOTE: This equipment is designed for indoor installation only.
Unit Start-Up
1. Set the primary controller to the highest setting.
2. Set the primary controller system switch to “COOL.” The
reversing valve solenoid should energize. The compressor
should not run.
3. Reduce the primary controller setting approximately
5 degrees below return fluid temperature.
4. Verify the heat pump is operating in the cooling mode.
5. Check the cooling refrigerant pressures against the values
listed in Table 6.
6. Turn the primary controller system switch to the “OFF”
position. The unit should stop running and the reversing valve
should de-energize.
7. Leave the unit off for approximately (5) minutes to allow for
system equalization.
8. Turn the primary controller to the lowest setting.
9. Set the primary controller switch to “HEAT.”
10. Increase the primary controller setting approximately
5 degrees above the return fluid temperature.
11. Verify the heat pump is operating in the heating mode.
12. Check the heating refrigerant pressures against the values
listed in Table 7.
13. Set the primary controller to maintain the desired return fluid
temperature.
14. Check for vibrations, leaks, etc.
15. Instruct the owner on the unit and control operation.
Operating Limits
ENVIRONMENT
This equipment is designed for indoor installation ONLY. Extreme
variations in temperature, humidity and corrosive water or air will
adversely affect the unit performance, reliability and service life.
(See Table 8.)
POWER SUPPLY
A voltage variation of ± 10% of nameplate utilization voltage is
acceptable.
NOTE: These operating conditions are not normal or continuous
operating conditions. It is assumed that start-up is for the purpose
of bringing the building space up to occupancy temperature. (See
Table 8.)
IMPORTANT: Operation of unit in test mode can lead to
accelerated wear and premature failure of components. The
"TEST" switch must be set back to "NO" after troubleshooting/
servicing.
WARNING
When the disconnect switch is closed, high voltage is present
in some areas of the electrical panel. Exercise caution when
working with the energized equipment.