Startup
44
RT-SVX34F-EN
predetermined time at the previous unit function's
minimum speed. All other cases which would bring the
Supply Fan ON will function as on non-Single Zone VAV
units.
Supply Fan Mode ON Operation
For active unit control with the Supply Fan Mode set to ON,
the unit will energize the Supply Fan and hold the Fan
Speed output at minimum speed until there is a request for
the fan speed to increase. This will hold true for all cases
except during Unoccupied periods in which the Supply
Fan Mode is forced to AUTO and will operate the Supply
Fan as described above for all Cooling, Heating, and
Dehumidification requests.
Setpoint Arbitration
Single Zone VAV units will require traditional Zone
Heating (if Heat installed) and Cooling Setpoints that are
used constant volume units in addition to two new
setpoints: Discharge Air Cool (DA Cool - Fan SPD) and
Discharge Air Heat (DA Heat) Setpoint limits. The Zone
Heating and Cooling Setpoints will be selectable via the
existing RTRM customer connections for a Zone Sensor
panel and the DA Heat and Cool Setpoints will be customer
selectable via two onboard potentiometers on the RTOM
with ranges 50-150°F and 40-90°F respectively.
Table 22
and
Table 23
below can be used as a reference
when setting the DA Heat (R42) and DA Cool - Fan SPD
(R136) setpoints on the RTOM. Note that the
recommended settings for these setpoints is 100°F for the
DA Heat Setpoint and 50°F for the DA Cool - Fan SPD
Setpoint:
Note:
The above potentiometer voltage readings can be
verified via the provided test points located next to
each potentiometer. Use a DC voltmeter to the Vdc
reading between those points and common.
Ventilation Control
Units configured for Single Zone VAV control require
special handling of the OA Damper Minimum Position
control in order to compensate for the non-linearity of
airflow associated with the variable supply fan speed and
damper combinations.
Demand Controlled Ventilation
Units configured for SZVAV and Demand Controlled
Ventilation (CO2 sensor value available) require a new
control scheme comprised of 2 existing schemes that have
been traditionally mutually exclusive; DCV and OA CFM
Compensation.
Units configured with DCV will invoke the new Demand
Controlled Ventilation scheme which allows variable Bldg.
Design and DCV Minimum Positions and OA Damper
Table 22. DA heat setpoint
Volt-
age
(Vdc)
Set-
point
(ºF)
Volt-
age
(Vdc)
Set-
point
(ºF)
Volt-
age
(Vdc)
Set-
point
(ºF)
Volt-
age
(Vdc)
Set-
point
(ºF)
0.00
50
0.98
75
1.61
100
2.06
125
0.09
51
1.00
76
1.63
101
2.08
126
0.13
52
1.03
77
1.66
102
2.09
127
0.16
53
1.06
78
1.69
103
2.11
128
0.20
54
1.08
79
1.71
104
2.12
129
0.24
55
1.11
80
1.72
105
2.13
130
0.28
56
1.13
81
1.74
106
2.13
131
0.31
57
1.16
82
1.76
107
2.14
132
0.35
58
1.18
83
1.78
108
2.16
133
0.39
59
1.21
84
1.79
109
2.17
134
0.42
60
1.23
85
1.81
110
2.19
135
0.46
61
1.26
86
1.83
111
2.20
136
0.50
62
1.28
87
1.84
112
2.21
137
0.53
63
1.31
88
1.86
113
2.23
138
0.57
64
1.33
89
1.88
114
2.24
139
0.61
65
1.36
90
1.89
115
2.25
140
0.65
66
1.38
91
1.91
116
2.26
141
0.68
67
1.41
92
1.93
117
2.28
142
0.72
68
1.43
93
1.95
118
2.29
143
0.76
69
1.46
94
1.96
119
2.30
144
0.79
70
1.48
95
1.98
120
2.32
145
0.83
71
1.51
96
2.00
121
2.33
146
0.87
72
1.53
97
2.01
122
2.34
147
0.90
73
1.56
98
2.03
123
2.36
148
0.94
74
1.58
99
2.05
124
2.37
149
2.40
150
Table 23. DA cool - fan SPD setpoint
Setpoint
(°F)
Voltage
(Vdc)
Setpoint
(°F)
Voltage
(Vdc)
40
<0.1
55
1.65
41
0.2
56
1.7
42
0.3
57
1.75
43
0.45
58
1.83
44
0.55
59
1.9
45
0.7
60
1.95
46
0.8
61
2
47
0.95
62
2.05
48
1.05
63
2.1
49
1.15
64
2.13
50
1.25
65
2.17
51
1.3
66
2.21
52
1.35
67
2.27
53
1.45
68
2.3
54
1.55
69
2.35
70
>2.4
Table 22. DA heat setpoint
