Carrier 50TJ016-028 Installation, Start-Up And Service Instructions Manual page 14

Table 5 — EconoMi$er Switchover
Control Strategy
ECONOMI$ER
SWITCHOVER
Outdoor Air Outdoor Air
STRATEGY
Temperature
Dry Bulb X
Single
Enthalpy
Differential
X
Temperature
Differential
Enthalpy*
*Must be selected manually.
DRY BULB CHANGEOVER SET UP — Determine the dry
bulb changeover set point from Table 6. The settings are A, B,
C and D. Locate the ECON SP potentiometer and set the dry
bulb changeover set point. See Fig. 16. When the OAT is above
this set point, the damper is limited to minimum position
setting.
LEGEND
COM — Common
DAT — Discharge Air Thermistor
DM — Damper Motor
GND — Ground
OAH — Outdoor-Air Enthalpy Sensor
OAT — Outdoor-Air Temperature Sensor
POT — Potentiometer
RAH — Return-Air Enthalpy Sensor
RAT — Return-Air Temperature Sensor
REM — Remote
*OAT sensor shipped with EconoMi$er option. OAH, RAT, RAH and CO
SENSORS REQUIRED
Return Air Return Air
Enthalpy Temperature Enthalpy
X
X
X X
Fig. 23 — Typical EconoMi$er Sensor Wiring
If a potentiometer fails, its setting will default to the values
in Table 7.
Table 6 — Changeover Set Points
SETTINGS
Dry Bulb (°F)
Single Enthalpy* (Btu/lb)
Differential Temperature*
(°F, Not Adjustable)
Differential Enthalpy*
(Btu/lb, Not Adjustable)
*Field-installed accessory.
Table 7 — Default Potentiometer Settings
POTENTIOMETER
CO SP (PPM)
2
MECH CLG LOCKOUT
ECON SP
MIN POS (%)
are field-installed accessories.
2
14
A B C D
73 69 66 63
27 25 24 22
2 2 2 2
1 1 1 1
DEFAULT SETTING
1,000
50 F
D
20