Carrier AquaForce 30XV140 - Outside Air Temperature Reset

35
OUTSIDE AIR TEMPERATURE RESET — The control
system is capable of temperature reset based on outdoor-air
temperature (OAT). Typically as the outdoor temperature de-
creases so does building cooling load. The chilled water tem-
perature can be increased to lower energy usage while still
meeting load demand.
To use Outdoor Air Temperature Reset, four variables must
be configured: Cooling Reset Select, OAT No Reset Value
(outdoor temperature at which no reset is required), OAT Full
Reset Value (outdoor temperature at which full reset is re-
quired), and Cooling Reset Deg Value (the amount of tempera-
ture reset desired).
To configure this option with the Touch Pilot™ display:
In the example in Fig. 32, the outdoor air temperature reset
provides 0° F (0° C) chilled water set point reset at 85 F
(29.4 C) outdoor-air temperature and 15° F (8.3° C) reset at
55 F (12.8 C) outdoor-air temperature.
DISPLAY NAME PATH VALUE
Cooling Reset
Select
0=None, 1=OAT
2=Delta T,
3=4-20mA control
4=Space Temp
Main Menu

Configuration Menu 
Reset Configuration
Low = 0° F (0° C)
Default = 0° F (0° C)
High = 4 F (2.2 C)
OAT No Reset
Value
Low = 14 F (7.8 C)
Default = 14 F (7.8 C)
High = 125 F (69.4 C)
OAT Full Reset
Value
Low = 14 F (7.8 C)
Default = 14 F (7.8 C)
High = 125 F (69.4 C)
Cooling Reset
Deg. Value
Low = 30 F (16.7 C)
Default = 0° F (0° C)
High = 30 F (16.6 C)
0
2
4
6
8
10
12
14
16
Outdoor Temperature (deg F)
Reset Amount (deg F)
Cooling Reset
Deg. Value
= 15 F (8.3 C)
(cr_deg)
OAT No Reset Value
= 85 F (29.4 C)
(oat_hrno)
OAT Full Reset Value
= 55 F (12.8 C)
(oat_hrfu)
20 40 60 80 100 120 0
a30-5887
Fig. 32 — Example: OAT Temperature Reset