FBVi-2U4-4T |
FBVI-2U4-4T Contr
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Subject to change without notice
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73
M
AN
01
48
re
v 5
•
If the discharge air temperature is configured and DualMax control is enabled:
o
As heating demand rises from 0-50%, the discharge air temperature shall be reset
upwards, to a maximum of 20 deg above zone temperature. The stages of heat shall be
enabled to maintain the discharge air temperature setpoint.
o
As heating demand rises from 51-100%, the airflow setpoint shall reset from the
minHeatFlowStpt (A230)
to the
maxHeatFlowStpt (A229)
flow.
o
The duct coil shall control the VAV discharge air temperature to the setpoint. The duct coil
shall not directly control zone temperature.
Typically, the modulating heating valve may be controlled by either
AO-14
or
DO-09
and
D0-10
in a tri-
state control mode where
DO-09
drives the hot water valve open and
DO-10
drives it closed. There are
additional options available such as having
AO-14
as the first stage modulating heat and
AO-15
as the
second stage modulating heat.