EMI CAC_36, Инструкция по установке, эксплуатации и обслуживанию

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Cassette Air Handler
38
TROUBLESHOOTINg pROCEdURE
Continued
INFRARED CONTROLLER W/ OpTIONAL WALL THERMOSTAT
INTERCONNECT DIAgRAM – MODELS CAHB12, CAHB24, AND CACB36
Figure #13
pOWER SUppLY CHECK
When troubleshooting any EMI product, it
is important to first check the rating plate
for proper field voltage and breaker size.
With a voltmeter, check the incoming pow
-
er supply to see that it matches the rat
-
ing plate. The incoming power should not
exceed the nameplate voltage. Also, the
incoming power should not be below the
minimum voltage stated on the rating plate
(197 Vac for units rated 208/230 Vac).
A check for low voltage power should also
be made. By placing a voltmeter across
low
Volt terminals “R” and “C” at the indoor
unit, there should be a reading of 24 Vac.
LOW vOLT CONTROLS
The Cassette air handler, outdoor unit and
optional wall mounted thermostat (*) are
connected using low Volt (24 Vac), 18 AWG
interconnect wiring. The interconnect wiring
provides control communication between
each device. A 24 Vac transformer located
in the indoor air handler unit provides low
Volt control power to the system. All low
Volt wiring must be routed away from sharp
edges or objects that might otherwise dam
-
age the wiring. For proper interconnect wir
-
ing refer to Figures #12 or #13 .
The 24 Vac power supply can be measured
by placing a voltmeter across low V
olt ter-
minals “R” and “C” of the indoor or outdoor
unit. If 24 Vac is not present, check to en
-
sure that the high
Volt power is supplied to
the indoor unit.
(*)
NOTE:
For units with the optional Infrared
Hand Held Controller, a wall thermostat is not
required.