Auto-Zone Control Systems Auto-Zone Plus Systems Installation & Operation (Version 03A) - Manual (Page 173)

Auto-Zone Plus Section 4
Start-Up and Troubleshooting 4-23
2.0 Zone Manager
Overview
2.1 How It Works
2.1.1 Initialization
On system powerup the Zone Manager will go through the following process:
• Initial startup delay of one minute.
• Bypass damper open relay activates.
• Bypass damper close relay activates.
This bypass damper close relay should remain active for at least 30-45 seconds.
(See Bypass Troubleshooting Procedures if the relay only remains active for 15
seconds)
• Bypass damper opens to twenty-five percent in preparation for fan start.
If either the bypass open or the bypass close relays continue to energize with
increasing ON duration, see bypass troubleshooting procedures. It is abnormal for
the bypass open or closed relays to energize for longer than a few seconds at any
time except during calibration, morning startup, or end of day shutdown.
• Fan relay activates.
After calibration, zones are initialized, then the FAN can start if one of the
following conditions exist:
∗ If the schedule is currently in the occupied period.
∗ There is a heat or cool demand if the unit is in unoccupied period.
∗ An override is in effect.
• During this initialization period, the controller retrieves all operating setpoints from
its non-volatile EEPROM memory and initializes all outputs to an OFF condition.
2.1.2 Calibration
At the conclusion of the fifty second startup delay, the system will proceed with the
Bypass Damper calibration. Depending upon the degree of travel and the speed of the
damper actuator, this process could take up to a maximum of four minutes. The Static
Pressure Null Voltage is read at the factory during powerup checks before shipping. If the