American Standard YK-IOM-2, Установка, эксплуатация и обслуживание

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Diagram Improper Electrical Phase Sequence
Proper compressor motor electrical phasing can be quickly de-
termined and corrected before starting the unit. Use a quality
instrument such as an Associated Research Model 45 Phase
Sequence Indicator and follow this procedure.
1. Open the electrical disconnect or circuit protection switch
that provides line power to the High Voltage Terminal Block
(HTB1) in the control panel.
2. Connect the phase sequence indicator leads to the HTB1
as follows:
Phase Seq. Lead HTB1 Terminal
Black (Phase A) L1
Red (Phase B) L2
Yellow (Phase C) L3
Bodily injury can result
from high voltage electrical components. If operating
checks must be performed with the unit operating, it
is the technician’s responsibility to recognize these
hazards and proceed safely. Failure to do so could
result in severe personal injury or death due to
electrical shock or contact with moving parts.
3 . Read the phase sequence on the indicator after turning
power on by closing the unit disconnect switch. The “ABC” in-
dicator on the face of the phase indicator will glow if phase is
ABC.
4. If the “CBA” indicator glows instead, open the unit main dis-
connect and interchange any two main line leads on HTB1. re-
close the unit main disconnect and recheck phasing.
5. Open units main disconnect before continuing with installa-
tion.
6. Disconnect the phase indicator.
Open and lock unit
disconnect switch before continuing installation.
Failure to do so could result in severe personal injury
or death due to electrical shock or contact with
moving parts.
Note: If a phase indicator is not available, follow the
electrical phasing sequence in the cooling start-up
section to insure proper compressor rotation.
IMPORTANT: After completion of wiring, check all
electrical connections, including factory wiring within
the unit, and ensure all connections are tight. Replace
and secure all electrical box covers and access doors
before leaving unit or connecting power to circuit
supplying unit.
After all electrical wiring is complete, SET THE ZONE SEN-
SOR SWITCH TO THE OFF POSITION AND THE FAN
SWITCH TO AUTO SO COMPRESSOR AND FAN WILL NOT
RUN, and apply power by closing the system main disconnect
switch. This will activate the compressor crankcase heaters.
Do not change the zone sensor setting until power has been
applied long enough to evaporate any liquid refrigerant in the
compressor. It is recommended the crankcase heaters be en-
ergized for 8 hours prior to starting.
Exception - Both circuits on the125 thru 250 units are not
equipped with crankcase heaters.
Start-Up
Pre-Start Quick Check List
[ ] Is unit properly located and level with proper clearances?
See Figure 1A and 1B.
[ ] Is the duct work correctly sized, run, taped, insulated and
weather proofed with proper unit arrangement? (See duct
work installation)
[ ] Is the gas piping correctly sized, run, and purged of air?
(See gas piping)
[ ] Is condensate line properly sized, run, trapped and
pitched?
[ ] Is the filter of the correct size and number, clean and in
place?
[ ] Is the wiring properly sized and run in according to the unit
wiring diagram?
[ ] Are all wiring connections tight including those in unit and
compressor electrical boxes?
[ ] Has the unit been properly grounded and fused with the
recommended fuse size? (see wiring data)
[ ] Is the zone temperature sensor correctly wired and in a
good location?
[ ] Have the air conditioning systems been checked at the
service ports for charge and leak tested if necessary?
[ ] Does the condenser fan and indoor blower turn freely
without rubbing and are they tight on the shafts?
[ ] Has the indoor blower speed been determined and the
proper speed been set? (See air flow performance data)
[ ] Has all work been done in accordance with applicable local
and national codes?
[ ] Are all covers and access panels in place to prevent air
loss and safety hazards?
Bodily injury can result
from high voltage electrical components. If operating
checks must be performed with the unit operating, it
is the technician’s responsibility to recognize these
hazards and proceed safely. Failure to do so could
result in severe personal injury or death due to
electrical shock or contact with moving parts.