Start-Up

Sequence of Operation

Tracer ZN Controller Sequence of Operation

Controller Start-Up

Refer to Trane publication CNT-SVX04A-EN, Installation, Operation, and Programming Guide, to operate the Tracer™ ZN controller with Trane Integrated Comfort™ System (ICS). The factory pre- programs the Tracer ZN controller with default values to control the temperature and unit airflow. Use Tracer Summit® building automation system or Rover™ software to change the default values.

Follow the procedure below to operate the Tracer™ ZN controller in a stand-alone operation:

1.Turn power on at the disconnect switch option.

2.Position the fan mode switch to either high, low, or the auto position.

3.Rotate the setpoint dial on the zone sensor module to 55°F for cooling or 85°F for heating.

The appropriate control valve will actuate assuming the following conditions:

1.Room temperature should be greater than 55°F and less than 85°F.

2.For a two-pipe unit with an automatic changeover sensor, the water temperature input is appropriate for the demand placed on the unit. For example, cooling operation is requested and cold water (5° lower than room temperature) flows into the unit.

3.Select the correct temperature setpoint.

Note: Select and enable zone sensor temperature settings to prevent freeze damage to unit.

Power-Up Sequence

When 24 VAC power is initially applied to the Tracer™ ZN controller, the following sequence occurs:

all outputs are controlled off

Tracer reads all input values to determine initial values,

the random start time (0–25 seconds) expires, and

normal operation begins.

Tracer ZN Modes of Operation

Tracer™ ZN controllers operate the fan in one of the modes listed below as noted:

occupied

unoccupied

occupied standby (Tracer ZN510 or ZN520 only)

occupied bypass

Tracer Summit® with supply fan control (Tracer ZN510 or ZN520 only)

Note: The Tracer™ ZN520 controller operates the supply fan continuously when the controller is in the occupied and occupied standby modes, for either heating or cooling. The controller only cycles the fan off with heating and cooling capacity in the unoccupied mode.

When the communicated occupancy request is unoccupied, the occupancy binary input (if present) does not affect the controller’s occupancy. When the communicated occupancy request is occupied, the controller uses the local occupancy binary input to switch between the occupied and occupied standby modes.

Occupancy Sources

There are four ways to control the Tracer™ ZN controller’s occupancy, as noted below:

1.By pressing the zone sensor’s timed override “on” button

2.Occupancy binary input, either normally open or normally closed, see Table 18 for occupancy sensor states

48

BCXC-SVX01B-EN

Page 48
Image 48
Trane BCVC, BCHC, BCXC-SVX01B-EN manual Start-Up, Tracer ZN Controller Sequence of Operation