Indoor Fan - Carrier Fan Coil Integration Manual

Sequence of Operation

Indoor fan

You can configure the indoor fan to operate in any 1 of 3 Fan Modes:
•
Auto (default) - runs intermittently during both occupied and unoccupied periods
•
Continuous - runs continuously during occupied periods and intermittently during unoccupied periods
•
Always on - runs continuously regardless of occupancy
In the Continuous mode, the fan is turned on when one of the following is true:
•
It is in occupied mode, as detemined by its occupancy status
•
There is a demand for cooling or heating in the unoccupied mode
•
There is a call for dehumidification (optional)
When power is reapplied after a power outage, or when transitioning from unoccupied to occupied, you can
configure a delay of 5 - 600 (default 60) seconds before starting the fan. Configure as follows:
•
Fan On Delay defines the delay time (0 - 30 seconds, default 30) before the fan begins to operate after
heating or cooling is started and is automatically overridden if electric heat or DX cooling are active.
•
Fan Off Delay defines the delay time (0 - 180 seconds, default 120) the fan continues to operate after
heating or cooling stops.
If the condensate overflow alarm, the test mode is active, or a Fire / Smoke Shutdown alarm is active; the fan is
shut down immediately, regardless of occupancy state or demand. The fan continues to run as long as the cooling,
heating, DCV, or dehumidification is active. If the space temperature failure alarm, condensate overflow alarm, or
the test mode is active, the fan shuts down immediately, regardless of occupancy state or demand.
Automatic Fan Speed Control - The Fan Coil controls up to 3 fan speeds using a Fan Interface board or field-
installed relays. The fan motor operates at the lowest speed possible to provide quiet and efficient fan operation
with the best latent capability during cooling. The motor increases speed if additional cooling or heating is
required to reach the desired space temperature setpoint. The motor's speed increases as the space temperature
rises above the cooling setpoint or falls below the heating setpoint. The amount of space temperature increase
above or below the setpoint that is required to increase the fan speed is configurable. Also, the fan speed
increases as the Supply Air Temperature approaches the configured minimum or maximum SAT limits if DX
cooling or electric heat is active.
Configuring Automatic Fan Speed setpoints – When configured for more than 1 speed, the fan speed selection is
based on Space Temperature compared to the Effective Setpoints. For example, if configured for a 3-speed fan,
the fan will go to Medium speed when the Space Temp exceeds the Cool 1/ Heat 1 level. The setpoint graph
represents this as the yellow and light blue areas. The fan increases to High speed when the Space Temp exceeds
Cool 2/ Heat 2 level. These are represented by the orange and dark blue areas. Speed is reduced when the Space
Temp passes the same threshold, but includes a non-adjustable Hysteresis (differential) of 0.5 °F (.27 °C) for
both heating and cooling modes. All color bands (yellow, orange, light blue and dark blue) MUST be set to more
than 0.5 °F (.27 °C).
Manual Fan Speed Control - When you use the controller with the optional SPT sensor, the automatic fan speed
operation may be overridden from the SPT sensor (if applicable). You can select any available motor speed or
automatic operation.
Unoccupied Fan Cycling - When Unoccupied Fan Cycling is set to Enable (default), the controller operates the
Fan Coil
Integration Guide
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