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1520 Cliveden Ave, Delta BC V3M 6J8
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2815 Ben Lomond Drive, Santa Barbara, CA 93105
P: 604 517-3888
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888 855-8880
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F 604 517-3900
www.airtesttechnologies.com
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TR9230 VAV Zone Control For Temperature And CO
2
Sequence Of Operation
Setup
The sensor shall have the following preset but adjustable parameters that can be
adjusted through use of on-board keypad and display or via a PC interface. These
settings can also be preconfigured for the user by AirTest™ or a AirTest™ distributor.
ï
Space temperature set point for occupied mode is established. (factory setting is
74ºF)
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Setback set point is set for unoccupied or setback mode (factory setting of 78ºF)
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User adjustable temperature band is set (factory set at +-2ºF)
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Select lowest allowable temperature (factory set at 3ºF below setpoint). This will
establish the point at which space ventilation will be limited to prevent over cooling of
the space.
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Target cfm per person ventilation rate is set (factory set at 15 cfm/person) This will
establish the upper limit of the proportional control band for ventilation.
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Select range 100% (0-10 V) or 50% (0-5V) range for the combined CO
2
and
ventilation output. (Factory setting is 0-5 V)
Operation
1. The controller shall measure both space CO
2
and temperature, The controller will
provide a modulation control signal to the VAV box actuator or fan based on the
maximum value calculated for either temperature control using a PI control
algorithm or CO
2
using a proportional control algorithm designed to provide a
predetermined target cfm/person to the space (e.g. 15 cfm/person).
Temperatures for normal occupied mode shall be ___ºF . And zone ventilation
shall be controlled to ___ cfm/person.
2. If the demand for ventilation causes the temperature to drop below set point, the
controller shall provide a binary closed contact signal intended to activate a
heating coil in the VAV box to prevent over cooling of the space and to maintain
set point.
3. The controller shall also be designed to override the demand for ventilation if the
space temperature drops ___ ºF below the temperature setpoint.
4. Manual push buttons on the wall mount controller shall allow users to control the
deviation of the temperature setpoint adjustment to a limit of +/- ___ degrees
from the set point programmed into the controller. This adjusted setpoint will be
maintained until the system reverts to a setback mode. Upon returning from
setback the sensor shall control temperature based on the original programmed
setpoint until the buttons are adjusted again.
5. If indoor CO
2
concentrations drop to a level where it is clear there is no
occupancy in the space (within 50 ppm of baseline concentrations). The system
