Lennox PRODIGY2.0 User Manual

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13. Supply Air Delivery
13.1. Blower Delays
The following is summary of blower delay options, For more details refer to sections 3.3.9 and 3.3.10.
13.1.1. Gas / Electric Units
The blower default delay is 40 seconds (parameter 66  HT GAS BLR ON DELAY) after the gas valve is energized and a
default of 120 seconds (parameter 67  HT GAS BLR OFF DLAY) after the gas valve is deenergized. The blower
operates anytime a heat limit trips.
13.1.2. Electric / Electric Units
The blower on delay is set to 0 seconds. The blower is delayed off by default for 20 seconds (parameter 60  HT ELEC BL
OFF DLAY) after the electrical heating is terminated.
13.1.3. Cooling Operation
The default on and off delays are 0, but may be adjusted by parameter 79 (COOL BLR ON DELAY) or parameter 80
(COOL BLR OFF DELAY). The ondelay time period starts when the cooling demand is initiated. The offdelay time
period starts when the cooling demand is terminated.
13.2. Supply Constant Air Volume (CAV) Control Mode
Units with Constant Air Volume have single-speed motor with belt driven blower. The same air volume is delivered for all
operating modes (heating, cooling and ventilation) and stages. These units are indicated by blower type B in the model
number. All blower on and off delays described above still apply.
13.3. Supply Multi-Stage Air Volume (MSAV) Control Mode
Units with Multi-Stage Air Volume are capable of delivering two or more stages/volumes of supply air. There are three
blower types supported for Multi-Stage Air Volume:
 Belt driven blower with motors and external variable frequency drives – Blower type M in model number.
 Direct driven blower using motors with integrated variable frequency control – Blower type E in model number.
 Belt driven blower with two-speed motors  Blower type T in model number.
Refer to the unit parameter label, installation instruction or service manual for details on percentage outputs and factory
default CFM settings.
13.4. Variable Frequency Drive Control
The M3 unit controller is only compatible with the factory installed variable frequency drives used to control the supply
blower. The analog control for the variable frequency drives is 010VDC. This manual uses percent (%) for all blower and
fan speeds. For example, 50% blower speed equals 30Hz equals 5VDC. Output frequency to the motor is displayed on
the VFD drive seven-segment LEDs.
Table 35. Variable Frequency Drive Control
Speed % Motor Frequency (Hz)
Variable Frequency Drive Control
Voltage (VDC)
30 18 3
40 24 4
50 30 5
60 36 6
70 42 7
80 48 8
90 54 9
100 60 10

Lennox PRODIGY2.0 Specifications

General

Brand	Lennox
Model	PRODIGY2.0
Category	Controller
Language	English