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2.6.2- AC/HP size
Select System Size Installed
The factory setting for air conditioner or heat pump size is the
largest outdoor unit that can be used with the furnace. Installer
needs to select air conditioner or heat pump size to ensure that
airflow delivered falls within proper range for the size unit
installed.
The select pins are marked 3, 2 ½, 2, 1 ½ for furnace equipped
with ½ HP ECM motor and 5, 4, 3 ½, 3 for furnace equipped with
1.0 HP ECM motor. Refer to the unit wiring diagram and select
the pin for the outdoor unit size being used (Refer to Figure 10
and Figure 16).
2.6.3- System type
Select System Type Installed AC or HP
The type of system must be selected:
1.
AC
– Air Conditioner provides approximately 400 CFM per
ton for greater efficiency and humidity control with the
AC/HP CFM ADJUST set to the nominal (NOM) tap. To
achieve more or less than 400 CFM per ton, move tap to
(HI) or (LO) position respectively. Refer to appropriate
airflow tables for exact CFM setting.
2.
HP-COMFORT
– Heat Pump Comfort provides
approximately 350 CFM per ton for higher than normal
heating air delivery temperature.
3.
HP-EFF
– Heat Pump Efficiency provides same airflow for
heating and cooling modes to increase overall HP
efficiency; approximately 400 CFM per ton with the AC/HP
CFM ADJUST set to the nominal (NOM) tap.
The factory setting is AC (Refer to Figure 10 and Figure 16).
2.6.4- AC/HP CFM adjust
Select Medium, Low, or High Airflow
To provide airflow at rates described above, the AC/HP ADJUST
select is factory set to the nominal (NOM) tap. The adjust
selections HI/LO will regulate airflow supplied for all operational
modes.
HI provides 10% airflow over nominal unit size selected and LO
provides 10% airflow below nominal unit size selected.
Setting options are provided to adjust airflow supplied to meet
individual installation needs for such things as noise, comfort,
and humidity removal. (Refer to Figure 10 and Figure 16)
2.6.5- ON/OFF delay
Select desired time delay profile
NOTE:
Delay selections are active in cooling and heat pump
heating modes only. Electric heating modes have a one (1)
minute OFF delay at 50% airflow and zero (0) ON delay
programmed into the ECM motor that cannot be overridden.
Four (4) motor operation delay profiles are provided to
customize and enhance system operation. (Refer to Figure 10
and Figure 16).
Selection options are:
1.
0/90:
No ON delay and 90 second OFF delay at 100%
airflow (factory setting).
2.
30/90:
30 second ON delay with no airflow and 90 second
OFF delay at 100% airflow profile. Used when it is desirable
to allow system coils time to heat-up/cool-down in
conjunction with the airflow.
3.
0/0:
No delay option. Used for servicing unit or when a
thermostat is utilized to perform delay functions.
4.
ENH:
enhanced selection provides a 30 second ON delay
with no airflow followed by 150 seconds at 70% airflow, and
no OFF delay for added comfort. This profile will minimize
cold blow in heat pump operation and could enhance
system efficiency.
2.6.6- Continuous fan
NOTE:
If installed with a two-stage outdoor unit, do not select HI
speed continuous fan. If HI is selected, low stage compression
will also run HI fan speed possibly resulting in insufficient
dehumidification.
Select desired fan speed when thermostat is set on
continuous fan. (Refer to Figure 10 and Figure 16)
1.
LO speed
– factory setting, 50% cooling mode airflow.
2.
MED speed
– move connector to MED, 80% cooling mode
airflow.
3.
HI speed
– move connector to HI, 100% cooling mode
airflow.
2.6.7- Low-voltage circuit
Fusing and Reference
The low-voltage circuit is fused by a board-mounted 5-amp
automotive fuse placed in series with the transformer SEC2 and
the R circuit. The C circuit of the transformer is referenced to
chassis ground through a printed circuit run at SEC1 connected
to metal standoff marked with ground symbol.
2.6.8- Basic furnace configuration
The following basic configuration of the furnace will provide ARI
rated performance of an air conditioner:
1.
HEAT KW/CFM
– Select the heater range for the size
electric heater installed.
2.
AC/HP SIZE
– Select system size installed.
3.
SYSTEM TYPE
– Select system type AC
4.
AC/HP CFM ADJUST
– Select NOM.
5.
ON/OFF DELAY
– Select 0/90 profile.
6.
CONTINUOUS FAN
– Select desired fan speed when
thermostat is set to continuous fan.
The following basic configuration of the furnace will provide ARI
rated perform ance of a heat pump:
1.
HEAT KW/CFM
– Select the heater range for the size
electric heater installed.
2.
AC/HP SIZE
– Select system size installed.
3.
SYSTEM TYPE
– Select system type HP-EFF
4.
AC/HP CFM ADJUST
– Select NOM.
5.
ON/OFF DELAY
– Select 0/90 profile.
6.
CONTINUOUS FAN
– Select desired fan speed when
thermostat is set to continuous fan.
