Operation
47
RT-SVX19A-E4
Setting the economizer
or 0-50% motorized hood
(option)
The ECA board is mounted on the
damper actuator. To access the ECA
board on economizers:
• Remove the access panel located
on the economizer section.
• The electrical power must be
disconnected to set the
minimum position and check the
economizer.
• Disconnect the power supply,
put the thermostat fan selector
to "ON" and the "HEAT/COOL"
selector to "OFF". This puts the
damper in the minimum
ventilation position.
• To set the required minimum
ventilation air position, turn the
dial on the ECA clockwise to
increase ventilation, or anti-
clockwise to decrease ventilation.
The damper will open at this
setting whenever the fan circuit
is powered up.
• When the arrow on the dial
adjustment screw is pointing to 8
o'clock, the minimum position is
roughly 0%. When the dial is
pointing to 12 o'clock it is
roughly 25%, and when the dial
is pointing to 4 o'clock it is
roughly 50%
To check the damper is functioning
correctly, the ECA is equipped with
an indicator light in the middle of
the board. This light operates as in
Table 35.
Table 35 - ECA board LED
While setting the minimum position
the damper may move toward the
new setting in several small steps.
Once the damper has remained in
the same position for 10 to
15 seconds it can be assumed it is
in the new position.
OFF:
No Power or Failure
ON:
Normal, OK to Economize
Slow Flash:
Normal, Not OK to
Economize
Fast Flash:
Communications Failure
Pulse Flash: Error Code:
1 Flash:
Actuator Fault
2 Flashes:
C0
2
Sensor
3 Flashes:
RA Humidity Sensor
4 Flashes
RATemp Sensor
5 Flashes:
OA Quality Sensor
6 Flashes:
OA Humidity Sensor
7 Flashes:
OATernp Sensor
8 Flashes:
MATemp Sensor
9 Flashes:
RAM Fault
10 Flashes:
ROM Fault
11 Flashes:
EEPROM Fault
