Troubleshooting - General - ECR EMI America Series Installation, Operation And Maintenance Manual

WARNING
Service should be performed by a
fied service agency
check is recommended.
Electrical shock hazard
moving access panels or control covers
to expose moving parts of non-insulated
live electrical components for service,
disconnect all high-voltage power supplies
to both the indoor unit and outdoor unit.
Failure to do so could result in physical
injury and/or electrical shock.
Wiring diagram
When trouble-shooting the indoor unit,
please refer to the wiring diagram that is sup-
plied with the equipment.
• The wiring diagram is located on the
inside surface of the control panel cover
(see Figure 29, Page 23).
• If you are unable to locate the wiring
diagram, please call the factory technical
service line at (800) 228-9364, and one
can be faxed, mailed or e-mailed. Please
have the full model and serial number
available prior to calling.
Wiring requirements
EMI America Series evaporators are de-
signed to operate with EMI America Series
condensers.
• The air handle (indoor unit) and con-
denser (outdoor unit) must be indepen-
dently connected to the electrical service
Comfort where it counts
CACG/CAHG & CACH/CAHH
• Installation, Operation and Maintenance Manual •
Troubleshooting — General
quali-
and an annual system
— Before re-
panel and protected by separate time
delay fuse or HACR breakers. (See the
unit name plate for the correct breaker
type and size).
• The indoor and outdoor units are also
connected to each other via a 24V inter-
connect wiring. (Figure 42, Page 51 or
Figure 43, Page 51)
• A transformer provides the low-voltage
power source for the controls. The
number of low-voltage interconnect
conductors will be two to six depending
on heating options and or thermostat
selection.
• Interconnect wire should be at least
18 awg.
• Refer to the unit wiring diagram for the
interconnect diagram that matches your
system.
Power supply check
When troubleshooting any EMI product, it
is important to first check the rating plate for
proper field voltage and breaker size.
Then use a voltmeter to check the incoming
power supply to verify that it agrees with the
rating plate.
• The incoming power must not exceed the
nameplate voltage.
• The incoming power must not be below
the minimum voltage stated on the rating
plate (197V for units rated 208/230V and
104V for units rated 115V).
Also very low-voltage power — place a volt-
meter across low-voltage terminals R and C at
the indoor unit. The voltage should be 24V.
50
Air Handlers
P/N 240007756, Rev. A [051509]