Table of Contents
Advertisement
SYSTEM OPERATION
*PH MODELS EQUIPPED WITH EEM BLOWER MO-
TORS
With the thermostat set to the emergency heat position, R to
W1 will be energized. This will energize the electric heat se-
quencers and the EEM motor. The electric heat will be ener-
gized through the normally open contacts of the electric heat
sequencers. The indoor blower will be energized through W
from the thermostat.
DEFROST CYCLE
PACKAGE HEAT PUMPS
The defrosting of the outdoor coil is jointly controlled by the
defrost control board and the defrost thermostat.
SOLID STATE DEFROST CONTROL
During operation the power to the circuit board is controlled
by a temperature sensor, which is clamped to a feeder tube
entering the outdoor coil. Defrost timing periods of 30, 60, or
90 minutes may be selected by setting the circuit board
jumper to 30, 60, or 90 respectively. Accumulation of time for
the timing period selected starts when the sensor closes
(approximately 32 + 2° F), and when the room thermostat
ECM MOTOR
SPEED ADJUSTMENT
Each ECM blower motor has been preprogrammed for operation at 4 distinct air flow levels when operating in Cooling/Heat
Pump mode or Electric Heat mode. These 4 distinct levels may also be adjusted slightly lower or higher if desired. The
adjustment between levels and the trim adjustments are made by changing the dip switch(s) either to an "OFF" or "ON"
position.
DIP SWITCH FUNCTIONS
The ECM motor has an electronic control that contains eight (8) 2-position dip switches. The function of these dip switches
is shown in Table 6, Airflow charts pages 42 and 43.
For APC15 / APH16 [24-36] models, dip switch 4 must be set to ON. Dip switch 4 must be set to OFF for two-stage
compressor models APC15 / APH16 [48-60]. Dip switch 4 ON energizes Y1 signal to the ECM motor anytime Y/Y2 is
energized. The indoor motor will not operate properly if switch is not set correctly for the model.
THERMOSTAT "FAN ONLY" MODE
During Fan Only Operations, the CFM output is 50% of the high stage cooling setting.
HUMIDITY CONTROL
When using a Humidistat (normally closed), cut jumper PJ6 on the control board. The Humidistat will only affect both low
stage and high stage cooling air flow by adjusting the Air flow to 85%.
TWO-STAGE HEATING
When using staged electric heat, cut jumper PJ4 on the control
board.
THERMOSTAT WIRING
Use thermostat wiring diagrams provided with the thermostat when
making these connections.
*PC15/*PH16**H41*
calls for heat. At the end of the timing period, the unit's
defrost cycle will be initiated provided the sensor remains
closed. When the sensor opens (approximately 60° F), the
defrost cycle is terminated and the timing period is reset. If
the defrost cycle is not terminated due to the sensor tem-
perature, a twelve minute override interrupts the unit's defrost
period.
FAN OPERATION
CONTINUOUS FAN MODE
MODELS EQUIPPED WITH EEM BLOWER MOTORS
If the thermostat calls for continuous fan, the indoor blower
will be energized from the G terminal of the thermostat to the
EEM blower motor.
If a call for heat or cool occurs during a continuous fan call,
the EEM motor will always recognize the call for the highest
speed and ignore the lower speed call.
If the thermostat is not calling for heat or cool, and the fan
switch on the thermostat is returned to the automatic posi-
tion, the fan will stop after the programmed 60 second off
delay on units with the EEM motor.
DIP SWITCH NUMBER
1
2
3
4
5
6
7
8
FUNCTION
El ectri c Heat
N/A
Indoor Thermos ta t
Cool i ng & Hea t Pump CFM
CFM Tri m Adjus t
TABLE 6
19
Advertisement
Table of Contents
