Rheem RHPL-HM2421JC, Installation Instructions Manual

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CONVENTIONAL THERMOST
A
T WIRING
The RHPL-series air handler is shipped with “On Demand Dehumidification” (ODD)
turned OFF. On Demand Dehumidification is used in conjunction with a traditional
24VAC thermostat equipped with an on-board humidity sensor. Activate ODD by turn-
ing DIP switch 7 ON. ODD operation is controlled by the indoor humidity sensed at the
thermostat. Operation is:
Normal Humidity (humidity BELOW the thermostat set point):
High Humidity (humidity ABOVE the thermostat set point):
The RHPL air handler is programmed to provide maximum efficiency and optimum
humidity removal. When high humidity is detected, the air handler reduces cooling air-
flow defined in Table 9.
IMPORTANT: The DIP switches are active only when using conventional a 24VAC ther-
mostat. If using the Comfort Control
2
System™, refer to Section 5.17 for adjusting airflows.
(Refer to Section 5.9.)
N NO OT TE E:: ODD airflow adjustments are active for cooling operation only. They are
ignored when the heat pump is in heating mode or when electric heat is activated.
5.19 COOLING DELAY PROFILES
Cooling delay profiles are not available when the RHPL air handler is controlled using a
conventional 24VAC thermostat. These profiles are available only when the air handler
is wired for the Comfort Control
2
System™. Refer to Section 5.10 for Comfort Control
2
Cooling Delay Profiles wiring.
5.20 AIR HANDLER DIAGNOSTIC CODES
Descriptions of the air handler Comfort Control
2
diagnostic codes are provided below.
These codes can be displayed at the thermostat or via a diagnostic tool.
IMPORTANT: Air handler diagnostic codes are available at the thermostat when the
system is wired for Comfort Control
2
.
TABLE 10
SELECTION C EXPLANATION: ON DEMAND DEHUMIDIFICATION
SWITCH 7
POSITION ODD
INPUT
COOLING AIRFLOW - CFM
RHPL-HM2421
Y1
Y2
Y2 Y2
Y2
Y1 Y1 Y1
RHPL-HM3621 RHPL-HM4824 RHPL-HM6024
NONE 500 625 725 950 950 1300 1100 1350
24VAC 625 775 900 1200 1200 1625 1375 1675
ON
TABLE 9
ODD AIRFLOW REDUCTION
11
Figure X – On Demand Dehumidification DIP Switch
The (-)HPL-series air handler is shipped with “On Demand Dehumidification” (ODD) turned
OFF. On Demand Dehumidification is used in conjunction with a traditional 24VAC thermostat
equipped with an on-board humidity sensor. Activate ODD by turning DIP switch 7 ON. When
ODD is turned ON, the thermostat sends a 24VAC signal to the ODD input of the air handler.
Operation is:
Normal Humidity (humidity BELOW the thermostat set point):
Normal Humidity Result
A 24VAC signal is applied to
the ODD terminal
Full rated airflow is delivered
by the blower
High Humidity (humidity ABOVE the thermostat set point):
High Humidity Result
No signal applied to the ODD
terminal
Airflow is reduced by a preset
amount to increase latent
capacity
The (-)HPL air handler is programmed to provide maximum efficiency and optimum humidity
removal. When high humidity is detected, the air handler reduces cooling airflow defined in
Table X.X.
Air Handler Cooling Airflow
Reduction
2-ton 85%
3-ton
4-ton
5-ton
80%
Table X.X – ODD Airflow Reduction
IMPORTANT: The DIP switches are active only when using conventional a 24VAC
thermostat. If using serial communications, refer to section 5 for adjusting airflows.
11
Figure X – On Demand Dehumidification DIP Switch
The (-)HPL-series air handler is shipped with “On Demand Dehumidification” (ODD) turned
OFF. On Demand Dehumidification is used in conjunction with a traditional 24VAC thermostat
equipped with an on-board humidity sensor. Activate ODD by turning DIP switch 7 ON. When
ODD is turned ON, the thermostat sends a 24VAC signal to the ODD input of the air handler.
Operation is:
Normal Humidity (humidity BELOW the thermostat set point):
Normal Humidity Result
A 24VAC signal is applied to
the ODD terminal
Full rated airflow is delivered
by the blower
High Humidity (humidity ABOVE the thermostat set point):
High Humidity Result
No signal applied to the ODD
terminal
Airflow is reduced by a preset
amount to increase latent
capacity
The (-)HPL air handler is programmed to provide maximum efficiency and optimum humidity
removal. When high humidity is detected, the air handler reduces cooling airflow defined in
Table X.X.
Air Handler Cooling Airflow
Reduction
2-ton 85%
3-ton
4-ton
5-ton
80%
Table X.X – ODD Airflow Reduction
IMPORTANT: The DIP switches are active only when using conventional a 24VAC
thermostat. If using serial communications, refer to section 5 for adjusting airflows.
11
Figure X – On Demand Dehumidification DIP Switch
The (-)HPL-series air handler is shipped with “On Demand Dehumidification” (ODD) turned
OFF. On Demand Dehumidification is used in conjunction with a traditional 24VAC thermostat
equipped with an on-board humidity sensor. Activate ODD by turning DIP switch 7 ON. When
ODD is turned ON, the thermostat sends a 24VAC signal to the ODD input of the air handler.
Operation is:
Normal Humidity (humidity BELOW the thermostat set point):
Normal Humidity Result
A 24VAC signal is applied to
the ODD terminal
Full rated airflow is delivered
by the blower
High Humidity (humidity ABOVE the thermostat set point):
High Humidity Result
No signal applied to the ODD
terminal
Airflow is reduced by a preset
amount to increase latent
capacity
The (-)HPL air handler is programmed to provide maximum efficiency and optimum humidity
removal. When high humidity is detected, the air handler reduces cooling airflow defined in
Table X.X.
Air Handler Cooling Airflow
Reduction
2-ton 85%
3-ton
4-ton
5-ton
80%
Table X.X – ODD Airflow Reduction
IMPORTANT: The DIP switches are active only when using conventional a 24VAC
thermostat. If using serial communications, refer to section 5 for adjusting airflows.