Carrier A07049 Installation Instructions Manual page 42

Programmable Fan (programmable models only)
The fan output can be programmed based on period of the day. When
programming for each day and period the fan can be set to On or AUTO.
Dry Contact
On the programmable models, the dry contact that can be used for control of an
auxiliary device. The dry contact may be configured to be closed for a specific
number of minutes per hour for each period of the program schedule. This can
be used to operate a ventilator, damper, system blower, or other auxiliary device.
There are two terminals, D1 and D2.
If it is desired to operate a ventilator or other device, the D1 and D2 terminals
can be connected directly to the equipment. This will provide a closed contact
for the specified number of minutes per hour. See Option 19.
If timed control of the system blower is required, the dry contact can be used for
this function. The G terminal can be connected to one of the dry contact
terminals with the other terminal being connected to Rc and/or Rh for timed
control of the fan. Note that this is not the same as programmable fan Option 30.
See Wiring Diagrams for more information.
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