Carrier 50EJ, 50EW, 50EY, 50EK installation instructions Features with Thermostat Control of Unit

Fig. 10 Ð Condensate Drain Connections (Typical Roof Curb or Slab Mount Shown)

Step 6 Ð Controls Options Ð The control options that the units can provide are based on the following param- eters: CV (constant volume) or VAV (variable air volume) operation; stand-alone unit with ®eld-supplied sensors in- stalled (CV or VAV); as a system via the Carrier Comfort System (TEMP or VVT); optional electronic expansion board installed (CV or VAV); linked to the Carrier Comfort Net- work; and availability of a computer and software (Comfort Works, Building Supervisor, and Service Tool) to access the base control board. See Table 3.

NOTE: Access to the base control board allows unit occu- pancy schedules, unit timeclock, and various set points to be changed from their factory-de®ned default settings.

CONSTANT VOLUME APPLICATIONS Ð The standard CV unit is capable of being operated with either a Carrier- approved thermostat or a ®eld-supplied sensor. (See Price Pages for ordering information.)

Features with Thermostat Control of Unit

·two-stage heating (if installed)

·two-stage cooling

·control of unit using Y1, Y2, W1, W2, and G thermostat inputs

·control of the indoor fan

·outdoor air temperature/supply air temperature monitoring

·control of an outdoor air condenser fan based on outdoor air temperature

·control of modulating economizer damper to provide free cooling when outdoor conditions are suitable, using sup- ply air temperature as a control point

·control of the economizer damper and indoor fan to obtain unoccupied free cooling

·provide power exhaust output to an external power ex- haust controller

·support a ®eld test for ®eld checkout

·control of 2 stages of CV power exhaust

· compressor Time Guard (power up and minimum off and on times)

Additional features are provided by accessing the stand- ard unit control board via software with a computer. These features are:

·electronic expansion board features (if installed)

·compressor lockout during low supply air temperature

·control board diagnostics

·ability to change supply air set point (economizer control)

·ability to change high outdoor air temperature lockout set point (economizer control)

·ability to change power exhaust set points

NOTE: A CV unit without a thermostat requires a ®eld- supplied sensor for operation.

Features with Sensor Control of Unit (Stand-Alone Appli- cations Ð Unit control is limited to CV unoccupied default set points, 90 F for cooling, 55 F for heating. There are

3 sensor options available:

·T-57 sensor will monitor room temperature

·T-55 sensor will monitor room temperature and provide unoccupied override capability (1 hour)

·T-56 sensor will monitor room temperature, provide un- occupied override capability (1 hour), and provide a tem- perature offset of 5° F.

Standard features are:

·support of remote occupied/unoccupied input to start and stop the unit

·cooling capacity control of 3 stages using economizer and 2 compressors to maintain space temperature to an occu- pied or unoccupied set point

·enable heating (if installed) or cooling during unoccupied periods as required to maintain space temperature within the unoccupied set points

·adjustment of space temperature set points of ± 5° F when using a T-56 sensor

Table 3 Ð Controls Options and Con®gurations (Non-Thermostat Applications)

UNIT CONFIGURATION	DEFAULT COOLING		DEFAULT HEATING
UNITS RUNNING VERSION 1.0 UNIT CONTROL SOFTWARE
CV or VAV Unit with SPT Sensor	Unoccupied Cooling Ð 90 F (SPT)		Unoccupied Heating Ð 55 F (SPT)
	Occupied Cooling	Ð NA	Occupied Heating	Ð NA
CV Unit with SPT Sensor and Remote	Unoccupied Cooling Ð 90 F (SPT)		Unoccupied Heating Ð 55 F (SPT)
Start/Stop Switch	Occupied Cooling	Ð 78 F (SPT)	Occupied Heating	Ð 68 F (SPT)
VAV Unit Remote Start/Switch Only	Unoccupied Cooling Ð NA		Unoccupied Heating Ð NA
	Occupied Cooling	Ð 55 F (SAT)	Occupied Heating	Ð NA
VAV Unit with SPT Sensor and Remote	Unoccupied Cooling Ð 90 F (SPT)		Unoccupied Heating Ð 55 F (SPT)
Start/Stop Switch	Occupied Cooling	Ð 55 F (SAT)	Occupied Heating	Ð NA
UNITS RUNNING VERSION 2.0 UNIT CONTROL SOFTWARE
CV or VAV Unit with SPT Sensor	Unoccupied Cooling Ð 90 F (SPT)		Unoccupied Heating Ð 55 F (SPT)
	Occupied Cooling	Ð NA	Occupied Heating	Ð NA
CV Unit with SPT Sensor and Remote	Unoccupied Cooling Ð 90 F (SPT)		Unoccupied Heating Ð 55 F (SPT)
Start/Stop Switch	Occupied Cooling	Ð 78 F (SPT)	Occupied Heating	Ð 68 F (SPT)
VAV Unit Remote Start/Stop Switch Only	Unoccupied Cooling Ð 90 F (RAT)		Unoccupied Heating Ð 55 F (RAT)
	Occupied Cooling	Ð 55 F (SAT)	Occupied Heating	Ð 68 F (RAT)*
VAV Unit with SPT Sensor and Remote	Unoccupied Cooling Ð 90 F (SPT)		Unoccupied Heating Ð 55 F (SPT)
Start/Stop Switch	Occupied Cooling	Ð 55 F (SAT)	Occupied Heating	Ð 68 F (RAT)*

		LEGEND				*With DIP Switch No. 5 con®gured to OPEN (Occupied Heat Enabled).
CV	Ð	Constant Volume	SAT	Ð	Supply-Air Temperature	NOTE: Space temperature sensor and remote stop/switch are ®eld-supplied.
NA	Ð	Not Available	SPT	Ð	Space Temperature
RAT	Ð	Return-Air Temperature	VAV	Ð	Variable Air Volume

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