Balance Point Worksheet

50CR

 

 

 

70

Based on Entering Indoor Air of 70 Deg. F and Rated CFM

 

 

 

 

 

 

Building Heat Loss, 1000BTUH

Unit Integrated Heating Capacity,

 

60

 

 

 

 

 

 

 

 

 

50

 

 

 

 

 

 

 

 

1000BTUH

40

 

 

 

 

 

 

 

 

30

 

 

 

 

 

 

 

 

20

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

10

 

 

 

 

 

 

 

 

 

 

 

0

 

 

 

 

 

 

 

 

 

 

 

-20

-10

0

10

20

30

40

50

60

Outdoor Air Temp (Deg F)

060

048

042

036

030

024

C03008

Fig. 25 - 50CR Balance Point Worksheet

Step 6—Refrigerant Circuit

Inspect all refrigerant tubing connections and the unit base for oil accumulation annually. Detecting oil generally indicates a refrigerant leak.

If oil is detected or if low performance is suspected, leak test all refrigerant tubing using an electronic leak detector, or liquid-soap solution. If a refrigerant leak is detected, refer to Check for Refrigerant Leaks section.

If no refrigerant leaks are found and low performance is suspected, refer to Checking and Adjusting Refrigerant Charge section.

Step 7—Indoor Airflow

The heating and/or cooling airflow does not require checking unless improper performance is suspected. If a problem exists, be sure that all supply- and return-air grilles are open and free from obstructions, and that the air filter is clean.

Step 8—Metering Devices-TXV & Accurater Piston

This unit uses 2 types of metering devices. The outdoor metering device is a fixed orifice and is contained in the brass-hex body in the liquid line feeding the outdoor coils. The indoor metering device is a TXV-type device.

Step 9—Pressure Switches

Pressure switches are protective devices wired into control circuit (low voltage). They shut off compressor if abnormally high or low pressures are present in the refrigeration circuit. These pressure switches are specifically designed to operate with Puron (R-410A) systems. R-22 pressure switches must not be used as replacements for the Puron (R-410A) system.

C99097

Fig. 26 - Refrigerant Circuit

Step 10—Loss-of-Charge Switch

This switch is located on the liquid line and protects against low suction pressures caused by such events as loss of charge, low

26

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Image 26
Carrier 50CR installation instructions Indoor Airflow, Metering Devices-TXV & Accurater Piston, Pressure Switches