SYSTEM OPERATION
9
Circulator Blower Speed
The Airflow quantity is displayed as a number on the three
7 segment displays, rounded to the nearest 100 CFM. The
display alternates airflow amount and the system operating
status.
Each furnace has a “Maximum CFM” it is capable of
providing. All fan operations (Constant CFM, Cooling
Airflow Profiles, Low and High Stage gas heat airflow,
outdoor Air Conditioner / Heat Pump Airflow, etc.) are
based off of multipliers which are percentages of this
maximum CFM. Max CFM is as follows:
3 Ton Models 1400 CFM
4 Ton Models 1760 CFM (1650 CFM for 0803 Models)
5 Ton Models 2200 CFM
Setup Furnace Airflow: adjust the Gas Heating Airflow
menu (gAF) setting to the desired percentage of maximum
airflow. In most cases the default gas heat airflow
will provide a temperature rise near the middle of the
acceptable range. High Stage CFM can be calculated
by the following equation: CFM = Max CFM * Selected
Heating Airflow Percentage.
For Communicating Outdoor Units: Main airflow adjustment
is not required. The Outdoor unit will determine the
appropriate amount of indoor airflow to request. Airflow
Trims can be made if desired.
For Non-Communicating outdoor units, determine the
proper airflow (based off tonnage of) the outdoor unit. Most
cooling systems are designed to work with airflow between
350 and 450 CFM per ton. 400 CFM/TON is the industry
standard. Once desired airflow has been determined, see
Tonnage / Airflow table to identify the Tonnage Selection
that is closest to the desired airflow. This table is based
on 400 CFM per ton where Airflow = (400 CFM) x (Selected
Tonnage).
Example: if 1520 CFM is the desired airflow the
Tonnage Selection that matches this is 3.8
Enter the Tonnage (ton) menu either by using the on board
push buttons or phone application and select the Tonnage
Selection you identified.
Note: Trim is also available if additional
adjustment is required.
Tonnage
Selection
Airflow Tonnage
Selection
Airflow Tonnage
Selection
Airflow Tonnage
Selection
Airflow
1
400
2.3
920
3.6
1440
4.9
1960
1.1
440
2.4
960
3.7
1480
5
2000
1.2
480
2.5
1000
3.8
1520
5.1
2040
1.3
520
2.6
1040
3.9
1560
5.2
2080
1.4
560
2.7
1080
4
1600
5.3
2120
1.5
600
2.8
1120
4.1
1640
5.4
2160
1.6
640
2.9
1160
4.2
1680
5.5
2200
1.7
680
3
1200
4.3
1720
5.6
2240
1.8
720
3.1
1240
4.4
1760
5.7
2280
1.9
760
3.2
1280
4.5
1800
5.8
2320
2
800
3.3
1320
4.6
1840
5.9
2360
2.1
840
3.4
1360
4.7
1880
6
2400
2.2
880
3.5
1400
4.8
1920
Cooling Airflow Ramping Profiles
The multi-circulator blower also offers several custom
ON/ OFF ramping profiles. These profiles may be used to
enhance cooling performance and increase comfort level.
The ramping profiles are selected using the Cooling Airflow
Profile menu (if push buttons are used, use the CAP menu
to select the desired profile). Refer to the bullet points
below for a description of each ramping profile.
OFF
100% CFM
100% CFM
1 min
OFF
Figure 50
•
provides only an OFF delay of one (1) minute at 100% of the cooling demand
Profile A(1)
50% CFM
1/2 min
100% CFM
100% CFM
1 min
OFF
OFF
Figure 51
•
ramps up to full cooling demand airflow by first stepping up to 50% of the full
demand for 30 seconds. The motor then ramps to 100% of the required airflow. A one (1)
minute OFF delay at 100% of the cooling airflow is provided.
Profile B(2)
100% CFM
OFF
OFF
•
ramps up to 85% of the full cooling demand airflow and operates there for
approximately 7 1/2 minutes. The motor then steps up to the full demand airflow. Profile C
also has a one (1) minute 100% OFF delay.
Profile C(3)
Figure 52
OFF
OFF
•
ramps up to 50% of the demand for 1/2 minute, then ramps to 85% of the full
cooling demand airflow and operates there for approximately 7 1/2 minutes. The motor
then steps up to the full demand airflow. Profile D has a 1/2 minute at 50% airflow OFF delay.
Profile D(4 or 5)
Figure 53
In general lower heating speeds will: reduce electrical
consumption, lower operating sound levels of the blower,
and increase the outlet air temperature delivered to the
home if heatmode is running. If cooling mode is running
the same airflow adjustment will decrease the outlet air
temperature delivered to the home. The speeds available
allow the blower performance to be optimized for the
particular homeowner’s needs.
