Carrier 50ZHA024-060 instruction manual A-ControlConnections Sizes, B-ControlConnections Sizes

C

R

G

Y

O

W2

W3

Thermostat and subbase

BROWN

RED

GREEN

YELLOW

ORANGE

WHITE

VIOLET

Unit Control

Power

A05207

3.Insulate the temperature sensing device so that the outdoor ambient doesn’t affect the reading.

4.Locate the measured suction line pressure in the top row of Table 8 and the measured outdoor ambient temperature in the left column of the table. Based on the two values, determine the required suction line temperature.

5.If the measured suction line temperature is greater than the tabulated temperature, add charge in the system.

048 and 060 units:

1.	Measure discharge line pressure by attaching a gauge to the
	service port.
2.	Measure the liquid line temperature by attaching a temperature
	sensing device to it.
3.	Insulate the temperature sensing device so that the outdoor
	ambient doesn’t affect the reading.
4.	Refer to the required subcooling in Tables 4 and 5 to find the
	required subcooling based on the model size and the outdoor
	ambient temperature.
5.	Interpolate if the outdoor temperature lies in between the table
	values. Extrapolate if the temperature lies beyond the table
	range.
6.	Find the pressure value corresponding to the measured pres-
	sure on the compressor discharge line.
7.	Read across from the pressure reading to obtain the Liquid line
	temperature for a required subcooling.

Fig. 10A—Control Connections (Sizes 024-042)

8. Add charge if the measured	temperature is higher than the
liquid line temperature value	in the table.

C

R

G

Y

Y1

O

W2

W3

Thermostat and subbase

BROWN

RED

GREEN

YELLOW

PINK

ORANGE

WHITE

VIOLET

Unit Control

Power

9. Add charge using the service connection on the suction line of

the compressor.

HEATING MODE CHARGE

Do not attempt to adjust charge by cooling methods while in heat pump heating mode. Recover refrigerant and weigh in according to unit data plate refrigerant data.

Step 4—Indoor Airflow and Airflow Adjustments

NOTE: For cooling operation, the recommended airflow is 350 to 450 cfm per each 12,000 Btuh of rated cooling capacity.

Table 7 shows dry coil air delivery for horizontal discharge units. Tables 9-11 show pressure drops.

NOTE: Be sure that all supply- and return-air grilles are open, free from obstructions, and adjusted properly.

ELECTRICAL SHOCK HAZARD

Failure to follow this warning could result in personal injury or death.

Disconnect electrical power to the unit and install lockout tag before changing blower speed.

Airflow can be changed by changing the 24 volts lead connections of the blower motor.

Unit 50ZHA blower motors are factory wired for rated airflow operation.

A05208

Fig.10B—Control Connections (Sizes 048-060)

LOW CHARGE COOLING

024-042 units:

1.Measure suction line pressure by attaching a gauge to the service port.

2.Measure the suction line temperature by attaching a tempera- ture sensing device to it.

FOR 208/230-V BLOWER MOTORS

The motor lead speed connections are as follows:

SIZE	RATED AIRFLOW	HIGH AIRFLOW
024	Tap 1	Tap 3
030	Tap 2	Tap 4
036	Tap 1	Tap 3
042	Tap 2	Tap 4

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