Startup
RT-SVX34F-EN
57
Table 33. Test mode states for SZ VAV units with modulating dehumidification and staged heat
TEST
STEP
MODE
FAN VFD COMMAND
1
ECON
4
COMP
1
COMP
2
HEAT
1
HEAT
2
PUMPOUT
3
COOL
VALVE
REHEAT
VALVE
1
FAN ON
ON
58% (0 VDC)
MIN
OFF
OFF
OFF
OFF
OFF
100%
0%
2
ECONOMIZER
ON
58% (0 VDC)
OPEN
OFF
OFF
OFF
OFF
OFF
100%
0%
3
COOL 1
ON
86% (6.67 VDC)
MIN
ON
OFF
OFF
OFF
IN-CONTROL
100%
0%
4
COOL 2
2
ON
100% (10 VDC)
MIN
ON
2
ON
2
OFF
OFF
IN-CONTROL
100%
0%
5
COOL 3
ON
100% (10 VDC)
MIN
ON
ON
OFF
OFF
IN-CONTROL
100%
0%
6
REHEAT
ON
80% (5.24 VDC)
MIN
ON
ON
OFF
OFF
IN-CONTROL
50%
50%
7
HEAT 1
ON
100% (10 VDC)
MIN
OFF
OFF
ON
OFF
OFF
100%
0%
8
HEAT 2
ON
100% (10 VDC)
MIN
OFF
OFF
ON
ON
OFF
100%
0%
9
RESET
1.
For Traditional VAV units, the VFD Command when “In-Control” will be controlled based on Supply Air Pressure Requirements. For SZ VAV units, the
VFD Command will be at discrete points during Test Mode.
2.
For 27.5-35T units, both compressors will be energized during the Cool 2 Step. For 40-50T units, only Compressor 2 will be energized during the Cool
2 Step.
3.
The Reheat Pumpout relay will be energized any time the Reheat circuit is energized in active Cooling Mode.
4.
For units with Statitrac installed, the Exhaust Damper will track the Economizer position during Service Test Mode and the Exhaust Fan will be
energized once the Economizer rises above the Exhaust Enable Setpoint.
Table 34. Test mode states for traditional VAV units with modulating dehumidification and modulating heat
TEST
STEP
MODE
FAN VFD COMMAND
1
ECON
4
COMP 1 COMP 2
HEAT
OUTPUT PUMPOUT
3
COOL
VALVE
REHEAT
VALVE
VAV
BOX
5
1
VFD SIGNAL 100%
OFF
100% (10VDC)
CLOSED
OFF
OFF
OFF
OFF
100%
0%
ON
2
VFD SIGNAL 0%
OFF
0% (0 VDC)
CLOSED
OFF
OFF
OFF
OFF
100%
0%
ON
3
MIN VENT
ON
IN-CONTROL
MIN
OFF
OFF
OFF
OFF
100%
0%
ON
4
ECON TEST OPEN
ON
IN-CONTROL
OPEN
OFF
OFF
OFF
OFF
100%
0%
ON
5
COOL 1
ON
IN-CONTROL
MIN
ON
OFF
OFF
IN-CONTROL
100%
0%
ON
6
COOL 2
2
ON
IN-CONTROL
MIN
ON
2
ON
2
OFF
IN-CONTROL
100%
0%
ON
7
COOL 3
ON
IN-CONTROL
MIN
ON
ON
OFF
IN-CONTROL
100%
0%
ON
8
REHEAT
ON
IN-CONTROL
MIN
ON
ON
OFF
IN-CONTROL
50%
50%
ON
9
HEAT 1
ON
IN-CONTROL
MIN
OFF
OFF
50%
OFF
100%
0%
ON
10
HEAT 2
ON
IN-CONTROL
MIN
OFF
OFF
100%
OFF
100%
0%
ON
11
RESET
1.
For Traditional VAV units, the VFD Command when “In-Control” will be controlled based on Supply Air Pressure Requirements. For SZ VAV units, the VFD
Command will be at discrete points during Test Mode.
2.
For 27.5-35T units, both compressors will be energized during the Cool 2 Step. For 40-50T units, only Compressor 2 will be energized during the Cool 2
Step.
3.
The Reheat Pumpout relay will be energized any time the Reheat circuit is energized in active Cooling Mode.
4.
For units with Statitrac installed, the Exhaust Damper will track the Economizer position during Service Test Mode and the Exhaust Fan will be energized
once the Economizer rises above the Exhaust Enable Setpoint.
5.
Heating will not be energized during Service Test until the 6 minute VAV Box ON timer has expired.
