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17
Multi-zone Heat Pump Condensing Units
MULTI-ZONE CONDENSER SEQUENCE OF OPERATION
When the outdoor temperature falls below
35°F, compressor operation will cease. At
that point the unit will switch on the indoor
units electric heater to assume the heating
demand, (second stage of heat).
Note: For full operation the indoor unit
must have an electric heater.
(C) B RN
(W) WHT
(Y) BLK
(O) ORG
(R ) RED
(G) GRN
(R ) RED
(R ) RED
(O) ORG
(O) ORG
(G) GRN
(Yin) B LK
(W) WHT
(Y) YEL
(C) B RN
(W) WHT
(Y) YEL
(C) B RN
OPTIONAL WALL T'S TAT
I.D. UNIT
O.D. UNIT
Heat Pump Applications
�
��
��
WLHA Wall unit
** - Electric heat option
use a "C" terminal
* - Some thermostats do not
YE L (Y1)
WALL T'STAT
O.D. UNIT
(C) B RN
Y
R
*
C
I.D. UNIT
BLK (Y)
BRN (C)
RED (R )
(Y) YEL
LOW VOLTAGE
INTERCONNECT DIAGRAM
* S OME T"STATS MAY NOT
HAVE A "C" TER MINAL
GR N (G)
(R ) RED
(O) ORG
CAHB HEAT PUMP
OPTIONAL
O
�
Refer to the indoor unit for the proper low Volt interconnect wiring.
S2HA LOW VOLT INTERCONNECT DIAGRAMS
OPERATION AND MAINTENANCE
The EMI America Series outdoor section is
the compressor bearing unit of the system.
It operates at the command of the indoor
section or room thermostat. Therefore, the
operation will be described in the manual
pertaining to the indoor section. The S2HA will
cease compressor operation at 35°F outdoor
temperature. If in heating mode, the electric
heat will take over when the compressor
ceases operation.
EMI units are designed and constructed for
reliability and long life with minimal main
-
tenance. You can assure peak operating
efficiency by regularly inspecting for free air
passage into and through the coil. If debris
collect on the air coil, it should be cleaned by
"back-flushing" with a spray of water or vacu-
uming. TURN OFF POWER SUPPLY FIRST.
Outdoor units may be cleaned or waxed if
desired. Use a non-abrasive car wax.
Panels should remain on the unit at all times.
Service should be performed by a QUALI
-
FIED service agency only.
GENERAL RECOMMENDATIONS
Do not charge the straight cool units on
cold days unless weighing in the charge.
The heat pump systems may be charged
in heat cycle between 35 and 75°F. These
units use a heat cycle TXV and cannot
be charged to superheat; use weight or
subcooling method only.
Charging should be done with a dial-a-
charge or weighed in with a scale.
SPECIFIC CHANGES
All EMI products are subject to ongoing de-
velopment programs so design and specifi-
cations may change without notice. Please
consult the factory for more information.
NOTE: For more information, please visit
our web-site at www.enviromaster.com or
call 1-800-228-9364.