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10

OPERATION

Cooling, Unit With EconoMi$er X

For Occupied mode operation of EconoMi$er X, there

must be a 24-v signal at terminals R and OCC (provided

through PL6-3 from the unit’s IFC coil). Removing the

signal at OCC places the EconoMi$er X control in

Unoccupied mode.

During Occupied mode operation, indoor fan operation

will be accompanied by economizer dampers moving to

Minimum Position setpoint for ventilation. If indoor fan is

off, dampers will close. During Unoccupied mode

operation, dampers will remain closed unless a Cooling

(by free cooling) or DCV demand is received.

When free cooling using outside air is not available, the

unit cooling sequence will be controlled directly by the

space thermostat. Outside air damper position will be

closed or Minimum Position as determined by occupancy

mode and fan signal.

When free cooling is available as determined by the

appropriate changeover command (dry bulb, outdoor

enthalpy, differential dry bulb or differential enthalpy), a

call for cooling (Y1 closes at the thermostat) will cause

the economizer control to modulate the dampers open and

closed to maintain the unit supply air temperature at 50 to

55

_

F. Compressor will not run.

During free cooling operation, a supply air temperature

(SAT) above 50

_

F will cause the dampers to modulate

between Minimum Position setpoint and 100% open. With

SAT from 50

_

F to 45

_

F, the dampers will maintain at the

Minimum Position setting. With SAT below 45

_

F, the

outside air dampers will be closed. When SAT rises to 48

_

F,

the dampers will re-open to Minimum Position setting.

Should 100% outside air not be capable of satisfying the

space temperature, space temperature will rise until Y2 is

closed. The economizer control will call for compressor

operation. Dampers will modulate to maintain SAT at 50

to 55

_

F concurrent with Compressor 1 operation. The

Low Ambient Lockout Thermostat will block compressor

operation with economizer operation below 42

_

F outside

air temperature.

When space temperature demand is satisfied (thermostat Y1

opens), the dampers will return to Minimum Damper

position if indoor fan is running or fully closed if fan is off.

If accessory power exhaust is installed, the power exhaust

fan motors will be energized by the economizer control as

the dampers open above the EXH1 SET setpoint and will

be de--energized as the dampers close below the EXH1

SET setpoint.

Damper movement from full closed to full open (or vice

versa) will take between 1-1/2 and 2-1/2 minutes.

Heating With EconoMi$er X

During Occupied mode operation, indoor fan operation

will be accompanied by economizer dampers moving to

Minimum Position setpoint for ventilation. If indoor fan is

off, dampers will close. During Unoccupied mode

operation, dampers will remain closed unless a DCV

demand is received.

When the room temperature calls for heat (W1 closes), the

heating controls are energized.

Demand Controlled Ventilation

If a field-installed CO

2

sensor is connected to the

EconoMi$er X control, a Demand Controlled Ventilation

strategy will operate automatically. As the CO

2

level in

the space increases above the setpoint (on the EconoMi$er

X controller), the minimum position of the dampers will

be increased proportionally, until the Maximum

Ventilation setting is reached. As the space CO

2

level

decreases because of the increase in fresh air, the

outdoor-damper will follow the higher demand condition

from the DCV mode or from the free-cooling mode.

DCV operation is available in Occupied and Unoccupied

periods with EconoMi$er X. However, a control

modification will be required on the 48TC units to

implement the Unoccupied period function.

Table 8 – Damper Position Control, 2--Speed Fan Motor, Economizer Cooling Not Available

INPUT

OCC

0---V

24---V

24---V

24---V

24---V

Y1

0---V

0---V

24---V

24---V

0---V

Y2

0---V

0---V

0---V

24---V

0---V

W1

0---V

0---V

0---V

0---V

24---V

SUPPLY FAN

MOTOR SPEED

OFF

LOW

LOW

HIGH

HIGH

DAMPER POSITION

NO CO2 SENSOR

CLOSED

MIN POS

MIN POS

MIN POS

MIN POS

W/CO2 SENSOR

CLOSED

FROM

VENTMIN L

TO

VENTMAX L

FROM

VENTMIN L

TO

VENTMAX L

FROM

VENTMIN H

TO

VENTMAX H

FROM

VENTMIN H

TO

VENTMAX H

LLECO

N

--

01

S

I

Содержание EconoMiser X

Страница 1: ...1 Clearing Alarms 11 SAFETY CONSIDERATIONS Improper installation adjustment alteration service maintenance or use can cause explosion fire electrical shock or other conditions which may cause personal...

Страница 2: ...Nomenclature In addition to criteria in Table 1 all units equipped with a factory installed EconoMi er X display a 6 in the 14th position of the model number indicating the low leak economizer control...

Страница 3: ...ge parameter and configuration settings Using the Keypad with Menus To use the keypad when working with menus S Press the Up arrow button to move to the previous menu S Press the Down arrow button to...

Страница 4: ...Displays if not connected short or out of range DA TEMP _ _ __F 0 to 140_F Displays when Discharge Air sensor is connected and displays measured discharge temperature Displays _ _ __F if sensor sends...

Страница 5: ...t if DCV is used This is the ventilation for less than maximum occupancy of the space In AUTO mode dampers controlled by CFM VENTMIN L 3 7 V VENTMIN H 2 8 V ERV OAT SP 32_F 0 to 50_F increment by 1 On...

Страница 6: ...libration temperature sensor RA H CAL 0 RH 10 RH Allows for the operator to adjust for an out of calibration humidity sensor DA T CAL 0 0_F 2 5_F Allows for the operator to adjust for an out of calibr...

Страница 7: ...abel Type Description Top Left Terminal Block MAT MAT 20k NTC and COM Mixed Air Temperature Sensor polarity insensitive connection OAT OAT 20k NTC and COM Outdoor Air Temperature Sensor polarity insen...

Страница 8: ...he W7220 calculates the enthalpy and dew point using the OA temperature and humidity input from the OA sensor When the OA temperature OA humidity and OA dew point are all below the selected boundary t...

Страница 9: ...Hood Factory Option The outside air hood for factory option economizer is shipped in knock down form and requires field assembly See the base unit Installation Instructions for details on assembling a...

Страница 10: ...outside air temperature When space temperature demand is satisfied thermostat Y1 opens the dampers will return to Minimum Damper position if indoor fan is running or fully closed if fan is off If acc...

Страница 11: ...d start over Under the SYSTEM SETUP menu you can change the setpoints to the factory defaults Will I be able to see the LCD screen when it is in the unit The LCD screen has a backlight that is always...

Страница 12: ...012 Carrier Corp D 7310 W Morris St D Indianapolis IN 46231 Printed in U S A Edition Date 02 12 Manufacturer reserves the right to change at any time specifications and designs without notice and with...

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