5.3 240V AIRFLOW PERFORMANCE DATA – TWO SPEED AIR HANDLER (CONSTANT TORQUE MOTOR) - continued
Nominal
Single Speed Air Handler
Cooling
Nonimal
Motor
Capacity
Heat
Width
Capacity
Type
21
24
M
No Heater
21
24
M
13 kW Heater
21
36
M
No Heater
21
36
M
18 kW Heater
NOTE:
Constant torque motor speed changes
All constant torque motors have 5 speed tabs. Speed tab 1 is for continuous fan. Speed tab 2 (low static) and Speed tab 3 (high static) are for lower tonnage. Speed tab
4 (low static) and Speed tab 5 (high static) are for higher tonnage.
Constant torque air handlers are always shipped from factory at speed tab 5, except for -4824, which is set at speed tab 3.
The low static Speed tab 2 (lower tonnage) and 4 (higher tonnage) are used for external static below 0.5" WC. The high static Speed tab 3 (lower tonnage) and 5 (higher
tonnage) are used for external static exceeding 0.5" WC. Move the blue wire to the appropriate speed tab as required by the application needs.
• The airflow for continuous fan (Speed tab 1) is always set at 50% of the Speed tab 4.
• The above airflow table lists the airflow information for air handlers without heater and air handler with maximum heater allowed for each model.
• The following formula can be used to calculate the approximate airflow, if a smaller (N kw) than the maximum heater kit is installed.
Approximate Airflow = Airflow without heater - (Airflow without heater - Airflow with maximum heater) X (N kw/maximum heater kw)