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Do not change the "ADJ" tab position on the CFM
selection board as this will change your cooling CFM
previously selected.
To Set Heat Pump CFM:
The heat pump CFM setting is the same as the cooling CFM.
No additional CFM setting is required, however, you must
remove the jumper at the bottom of the connector board labeled
"HP" for heat pump operation (See Figure 9).
To Set Delay Profile:
Every unit has multiple cooling "blower off delay" profiles to
optimize system performance and efficiency. Refer to Table 13
for the regional climate in your area. Place the "DELAY" jumper
tap on the CFM selection board to the appropriate pin setting.
To Set Electric Heat CFM:
The blower speed required for the Electric Heat is different than
cooling.
Refer to Table 10 for the minimum required CFM for the electric
heater installed. Find the desired airflow in Tables 7 and 8. Set
the "Heat" Jumper on the CFM selection board to tap shown.
Fan Only CFM:
When the connection is made from "R" to "G", the fan only
mode is activated. In this mode, the blower will deliver 75% of
the cooling system CFM. This connection is factory set from the
manufacturer and cannot be field adjusted.
Figure 9: Control Board Speed Tap Location
Table 13: Delay Profile
Delay Tap
Jumper at "A"
Jumper at "B"
Jumper at "C"
Johnson Controls Unitary Products
W2
W1
R
Y/Y2
Y1
Regional Climate Type
Standard Setting
Humid Climate
Dry Climate
Table 13: Delay Profile
Delay Tap
Jumper at "D"
Operation
The following sequences of operation are based on using a
standard single-stage heat pump thermostat.
Cooling Sequence Of Operations
1.
If the fan switch on the thermostat is in the "ON" position, the
24 volts at "G" signals the ECM motor controller to operate
the blower at 75% of the rated airflow. If the fan switch on the
thermostat is in the "AUTO" position, the blower operates
only when there is a call for cooling by the thermostat.
2.
Thermostat calls for cooling, the 24 volts at "O" energizes the
reversing valve solenoid. The 24 volts at "Y1" signals the
ECM controller to operate the blower at high speed and
closes the contactor coil M1 after the anti-short cycle period
is complete. Power is supplied to the compressor and
outdoor fan motor, and the reversing valve switches to the
cooling position. When the fan switch on the thermostat is in
the "AUTO" position, the indoor blower motor is energized at
the high-speed cooling airflow.
3.
When the cooling demand is satisfied, the 24 volt "Y1"
signal is removed and the M1 contactor de-energized. If
the fan switch on the thermostat is in the "ON" position, the
blower will continue to run at 75% of the rated airflow. If the
fan switch is in the "AUTO" position, the blower will
continue to run for a short period as determined by the
"DELAY" jumper setting on the CFM Selector board.
Heating Sequence Of Operations
1.
If the fan switch on the thermostat is in the "ON" position, the
24 volts at "G" signals the ECM motor controller to operate
the blower at 75% of the rated airflow. If the fan switch on the
thermostat is in the "AUTO" position, the blower operates
only when there is a call for heating by the thermostat.
2.
If the thermostat calls for heating, the 24 volts at "Y" signals
the ECM controller to operate the blower at high speed and
closes the contactor coil M1 after the anti-short cycle
period is complete. Power is supplied to the compressor
and outdoor fan motor. When the fan switch on the
thermostat is in the "AUTO" position, the indoor blower
motor is energized at the heating airflow. The reversing
valve remains in the heating position.
3.
For units equipped with supplementary electric heat, 24
volts at "W" sends 24 volts to "W2" on the fan control
board. This signal also is sent through the defrost control
terminals "W" and "W6" and back to the fan control "W1".
The 24 volt signal energizes all stages of electric heat.
527929-BIM-F-0911
Regional Climate Type
Temperate Climate
21
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