Start-up
TruVu™ VAVB3
-E2
CARRIER CORPORATION ©2022
Installation and Start-up Guide
All rights reserved
64
Two-Position Hot Water / Steam Heating Heat
–
The controller operates a normally closed or normally open hot
water or steam valve connected to the discharge air heating coil. The valve opens and closes as needed to satisfy
the zone's heat
ing requirements. For ducted heat, the terminal’s heat supp
lements any heat from the primary air
source, but the terminal's SAT is controlled so that it does not exceed the
Maximum Heating SAT
(90°F (32.2°C)
default). For non-ducted (baseboard) heating, t
he valve is controlled to keep the zone’s temperature at th
e
heating setpoint.
Electric Auxiliary Heat
–
The controller ope
rates 1, 2, or 3 stages of electric heat. For ducted heat, the terminal’s
heat supplements any heat from the primary air source, but the terminal's SAT is controlled so that it does not
exceed the
Maximum Heating SAT
(90°F (32.2°C) default). For non-ducted (baseboard) electric heat, the stages
are controlled as needed to keep the zone’s temperature at the heating setpoint.
SCR Electric Heat
–
The controller modulates an SCR heat output connected to the SCR electric heat control
input. The output increases
as needed to satisfy the zone’s heating requirements. For ducted heat, the terminal’s
heat supplements heat from the primary air source, if it is in heating mode and is controlled so that the SAT does
not exceed the
Maximum Heating SAT
(90°F (32.2°C) default). For baseboard heating (non-ducted heat), the
SCR heat output modulates to keep the zone’s temperature at the heating
setpoint.
Combination Modulating Baseboard / Electric Heat
–
The controller can modulate a normally closed or normally
open hot water or steam valve connected to a perimeter baseboard radiation system and control up to 2 stages of
ducted electric heat. The valve modulates as needed to satisfy the zone's heating requirements. If the valve
cannot meet the load, then the terminal's ducted e
lectric heat is used. The terminal’s electric heater supplements
any heat from the primary air source, but the terminal's SAT is controlled so that it does not exceed the
Maximum
Heating SAT
(90°F (32.2°C) default).
CV Modulating Heat
–
The controller can modulate a normally closed or normally open hot water or steam or
steam valve connected to a perimeter baseboard radiation system or discharge air heating coil. The valve
modulates as needed to keep the zone's temperature at the heating setpoint. For ducted applications, the
terminal's SAT is controlled so that it does not exceed the
Maximum Heating SAT
(90°F (32.2°C) default). (Used
primarily on single-duct terminals with ducted modulating hot water or steam heat in health care [hospital]
applications, where discharge air temperature swings may be problematic.
CV Modulating Heat
may also be used
in all non-ducted modulating heating applications.)
Parallel Fan Heat On Delay
–
For Parallel Fan terminals only, the controller has a configurable
Parallel Fan Heat
On Delay
to save energy. During the delay period (15 minute default), only the fan operates to recycle heat from
the ceiling plenum. If the heating requirement is not met by the end of the delay, the auxiliary heat is used.
Fan Heat Off Delay
–
For fan-powered terminals, the controller has a configurable
Fan Off Delay
. After the heating
coil is de-energized, the fan continues to run for the length of the delay to deliver to the zone any heat stored in
the coil. The default delay of 120 seconds is optimal for a ducted hot water coil. For ducted electric heat coils, the
nominal delay is approximately 45 seconds. For baseboard and non-ducted heat, the delay should be set at 0.
This feature applies to parallel fan terminals in both occupied and unoccupied mode and series fan terminals in
the unoccupied mode if the air source fan is off.