![background image](http://html1.mh-extra.com/html/carrier/rtu-open-v3/rtu-open-v3_installation-and-startup-manual_2562508083.webp)
Appendix A: RTU Open Points/Properties in i-Vu®/Field Assistant
RTU Open v3
CARRIER CORPORATION ©2019
Installation and Start-up Guide
All rights reserved
79
Point Name/Description
Range
Compressor Stages
– The number of mechanical cooling stages.
Not displayed if
Unit Type
is set to
LC WeatherExpert
™.
D:
R:
One Stage
One Stage
Two Stages
Face Split Coil
– Applies only to 2-stage cooling unit with variable speed fan control, this
defines the type of cooling coil installed in the unit. The controller uses it to estimate
the temperature of the air leaving the active portion of the cooling coil during part-load
operation.
Not displayed if
Unit Type
is set to
LC WeatherExpert
™.
D:
R:
Yes
No/Yes
Economizer Exists
– Set to
Yes
to enable economizer control for units equipped with an
economizer damper.
D:
R:
No
No/Yes
Fan Control
– The type of fan control used on this unit.
Automatically set to
Variable Speed
if
Unit Type
is set to
LC WeatherExpert
™.
D:
R:
Single Speed
Single Speed
Two Speed
Variable Speed
VFD Input
– Defines the electrical control signal used by the Variable Frequency Drive’s
(VFD) input. Applies to
Variable Speed
fan control only.
D:
R:
2-10 Vdc
0-10 Vdc
2-10 Vdc
Max VFD Output
– The maximum output signal the control supplies to the VFD as a
percentage of its range. The balancer can set this to adjust the unit’s maximum airflow.
Applies to
Variable Speed
fan control only.
D:
R:
100%
33% to 100%
Min VFD Output
– The minimum output signal the control supplies to the VFD as a
percentage of its range. The balancer can set this to adjust the unit’s minimum airflow.
Applies to
Variable Speed
fan control only.
D:
R:
40%
33% to 100%
Dehum Min VFD Output –
The minimum output signal supplied by the control during
dehumidification as a percentage of its range. Applies only to
Variable Speed
fan
control.
D:
R:
60%
50% to 100%
Stage 1 SAT Stpt
– The VFD Supply Air Setpoint during stage 1 cooling.
Must be at least 4°F (2.2°C) greater than
Minimum Cooling SAT
.
D:
R:
57°F (13.9°C)
45 to 75°F
(7.2 to 23.9°C)
Stage 2 SAT Stpt
– The VFD Supply Air Setpoint during stage 2 cooling.
Must be at least 4°F (2.2°C) greater than
Minimum Cooling SAT
.
D:
R:
57°F (13.9°C)
45 to 75°F
(7.2 to 23.9°C)
Stage 3 SAT Stpt
– The VFD Supply Air Setpoint during stage 3 cooling.
Must be at least 4°F (2.2°C) greater than
Minimum Cooling SAT
.
D:
R:
56°F (13.3°C)
45 to 75°F
(7.2 to 23.9°C)
Reversing Valve Output
– The type of reversing valve this unit uses.
D:
R:
O
O/B
Heat Type
– The type of heating used by the unit.
D:
R:
Electric
Electric/Gas
Number of Heat Stages
– The number heat stages.
D:
R:
2
1 / 2 /0 (no heating)
Summary of Contents for RTU Open v3
Page 113: ......