BALL VALVE DIGITAL MANIFOLD PRESSURE TESTER

1. Overview

The Intelligent electronic refrigerant group instrument is an auxiliary instrument for the installation, testing, and maintenance of refrigeration equipment such as air conditioners and cold storage. The instrument features double pressure test, dual temperature test, digital readout, multi-unit switching, multi-mode function, and a built-in refrigerant database.

The instrument is constructed with high-strength engineering plastics and a flexible non-slip silicone design, making it solid and comfortable to hold. It incorporates a built-in 32-bit digital processing unit and a high-precision data acquisition unit, ensuring high data accuracy and stability. The large-size liquid crystal display with LCD backlight support provides clear and easy-to-read data, facilitating convenient operation. The long-life valve switch and 1/4-inch standard interface design ensure the instrument's durability and versatility.

The instrument can measure double pressure (gauge pressure) and dual temperature simultaneously. It offers automatic multi-unit pressure conversion and automatic temperature conversion between Celsius (°C) and Fahrenheit (°F) to meet different needs. With a built-in database of 93 kinds of refrigerant pressure-evaporation temperature, it can also calculate subcooling and superheat for direct reading of operating process data. Additionally, it tests vacuum measurement percentage and pressure leak measurement, recording leak time and speed. This multi-functional, accurate, and simply operated digital manifold is designed to assist users in performing their tasks effectively.

2. Safety Rules and Precautions

This manual provides instructions and warnings for the safe operation and maintenance of the instrument. Failure to use the meter in accordance with the manual may damage the instrument. This instrument strictly follows the IEC/EN61010-1 safety standards for design and production.

• The pressure measured by the digital manifold pressure tester is gauge pressure.
• Pressure testing ranges from -101 Kpa to 6 Mpa (-0.1 bar to 60 bar).
• The limit pressure is 10 Mpa (100 bar).
• The maximum operating pressure of the standard hose is 600 PSI (approximate 4.13 Mpa, 41.3 bar). The limit pressure for the hose is 3000 PSI (approximate 20.68 Mpa, 206.8 bar).
• Please confirm the rated pressure value of the tested equipment before testing. Do not use the instrument if it exceeds its specified range. If the packed hoses do not match the pressure requirement, suitable replacements may be used for testing.
• Do not use or store the instrument in high temperature, high humidity, flammable, explosive environments, or areas with strong electromagnetic fields.
• Please do not change the instrument's internal circuit to avoid damage to the instrument or potential danger.
• Please wear qualified protective equipment to protect the user during testing.
• Please use the instrument in a well-ventilated environment to prevent inhalation of toxic gases.

3. International Electrical Symbols

4. Product Specifications

Pressure Test:

• Type: Gauge pressure
• Units: Kpa; Mpa; bar; inHg; PSI
• Range: 0 Kpa – 6000 Kpa
• Resolution: 1 Kpa
• Accuracy: +/- 0.5%(FS) + 5dgt
• Overload Limit: 10000 Kpa (10 Mpa; 100 bar)

Vacuum Test:

• Type: Relative vacuum
• Units: Kpa; Mpa; bar; inHg; PSI
• Range: -101 Kpa – 0 Kpa
• Resolution: 1 Kpa

Temperature Test:

• Units: °C (Celsius), °F (Fahrenheit)
• Range: -40°C to 150°C (-40°F to 302°F)
• Resolution: 0.1°C (-40°C to 99.9°C), 1°C (100°C to 150°C); 0.1°F (-40°F to 99.9°F), 1°F (100°F to 302°F)
• Accuracy: +/- 0.5 °C + 2dgt; +/- 0.9 °F + 2dgt

Refrigerants: Built-in 93 kinds of refrigerants (According to American NIST standard)

5. Product Icon and Description

The instrument features a digital display and various buttons and valves. The following describes the numbered components:

Diagram showing the front panel of the Digital Manifold Pressure Tester with numbered components.1. Clamp-on temperature probe socket2. Clamp-on temperature probe socket3. LCD display4. Unit button: Pressure unit switch button5. Mode button: Test function mode switch button6. Run/Stop button: Test Control Button (In Leak Test Mode)7. Backlit button8. °C/°F button: Temperature unit switch button9. Zero button: Pressure display zero button10. R+/R- Refrigerant Type Selection Buttons: Switch to select different types of working refrigerants11. Power button12. Refrigerant observation window13. Low pressure valve (blue)14. High pressure valve (red)15. 1/4 inch low pressure inlet16. 1/4 inch high pressure inlet17. Pressure release valve18. Refrigerant inlet/vacuum pump inlet

Refrigerant List:

R11, R113, R114, R115, R116, R12, R123, R124, R125, R1270, R13, R134A, R14, R141B, R142B, R143A, R152A, R170, R21, R218, R22, R227EA, R23, R236EA, R245C, R245FA, R290, R32, R401A, R401B, R401C, R402A, R402B, R403A, R403B, R404A, R405A, R406A, R407A, R407B, R407C, R407D, R407E, R408A, R409A, R409B, R41, R410A, R410B, R411A, R411B, R412A, R413A, R414A, R414B, R415A, R415B, R416A, R417A, R418A, R419A, R420A, R421A, R421B, R422A, R422B, R422C, R422D, R423A, R424A, R425A, R426A, R427A, R428A, R438A, R448A, R449A, R452A, R50, R500, R501, R502, R503, R504, R507A, R508A, R508B, R509A, R600, R600A, R717, R744 (CO2), R1234.

Power Supply: 4 X 1.5V (SIZE AA/LR6)

Dimensions: 240*145*50mm

Weight: 950g

6. Function Instructions

6-1. Refrigerant Filling and Pressure Inspection

A. Turn off the blue valve (low pressure) and red valve (high pressure).

B. Power on the instrument. Ensure the LCD displays the pressure test status. If not, press the Mode button to switch to the correct mode.

LCD display showing pressure and temperature readings. Example: 25.0 °C, R 134A, -18.0 °C, 2500 kPa (High Pressure), 0 kPa (Low Pressure).

C. If clamp-on temperature probe accessories are connected, the real-time temperature will be displayed. Otherwise, no temperature will be shown.

D. Use the R+/R- buttons, Unit button, and °C/°F button to select the tested refrigerant and display units, respectively.

E. When the instrument is turned on, the high and low pressure display areas might show 10 digits. Press and hold the Zero button until the display returns to zero.

F. Connect the instrument to the refrigeration system according to the diagram. Pay attention to the direction of refrigerant flow.

Diagram of a refrigeration system: Compressor, Condenser, Thermal Expansion Valve, Evaporator. Arrows indicate refrigerant flowing from Compressor to Condenser, then to Thermal Expansion Valve, then to Evaporator, and back to Compressor. The manifold tester is connected between the Condenser/Thermal Expansion Valve and the Evaporator/Compressor, with connections to both high and low pressure sides. Arrows also show refrigerant flowing direction through the system and the instrument.

G. Turn on the refrigerant valve and gently press the pressure release valve to vent air from the connecting hose.

H. When the refrigeration system stops, turn on the high pressure valve (red valve), fill with a certain amount of refrigerant, and then quickly shut the valve.

I. Run the refrigeration system. Turn on the low pressure valve (blue valve) and fill the system with refrigerant. Vacuum operation is required if the system is filled initially or completely with refrigerant. Refer to the section on vacuum operation.

J. After filling is complete, shut the low pressure valve (blue valve) and the refrigerant valve. Allow the refrigeration system to run.

K. Shut down the refrigeration system. Ensure all valves are turned off. Disconnect the instrument between the refrigeration system and the source. Do not remove the high pressure valve connection until the pressure drops to a safe point. Then, turn off the instrument.

Note: The filling operation for different equipment or refrigerants may vary. Carefully read the specific operation requirements for filling to avoid damage to the user or equipment due to improper operation.

The instrument can display the corresponding Evaporation Temperature (EV) and Condensation Temperature (CO) during refrigerant pressure tests.

LCD display showing: Ev -18.0 °C, Co -18.0 °C, 2500 kPa, 2500 kPa. (R 134A displayed).

If clamp-on temperature probes are connected, the LCD will display the real-time temperature for T1 Sensor and T2 Sensor.

LCD display showing: T1 Sensor 25.0 °C, R 134A, T2 Sensor 25.0 °C, Ev -18.0 °C, Co -18.0 °C, 2500 kPa, 2500 kPa.

The instrument can calculate Superheat (SH) and Subcooling (SC) if the refrigerant is preset and clamp-on temperature probes are connected correctly. °C / °F conversion is done by pressing the MODE button.

LCD display showing: T1 Sensor 25.0 °C, R 134A, T2 Sensor 25.0 °C, SC 19.0 °C, SH 19.0 °C, 2500 kPa, 2500 kPa.

6-2. Vacuum Operation

A. Turn off the blue valve (low pressure) and red valve (high pressure).

B. Power on the instrument. Ensure the LCD displays the vacuum test status. If not, press the Mode button to switch to the correct mode.

LCD display showing: 0 kPa, 0 kPa.

C. Press the Unit button to adjust the reading unit.

D. When the instrument is turned on, the high and low pressure display areas might show 10 digits. Press and hold the Zero button until the display returns to zero.

E. Connect the instrument to the refrigeration system according to the diagram. Pay attention to the direction of refrigerant flow. (Connected clamp-on temperature probes will not affect the operation.)

Diagram of a refrigeration system: Compressor, Condenser, Thermal Expansion Valve, Evaporator, and Vacuum Pump. Arrows indicate refrigerant flowing from Compressor to Condenser, then to Thermal Expansion Valve, then to Evaporator, and back to Compressor. The manifold tester is connected to the system. A vacuum pump is connected to the low-pressure side or the manifold's vacuum inlet.

F. Turn on the blue valve (low pressure) and red valve (high pressure), and start the vacuum pump.

G. After the vacuum operation is completed, turn off the blue valve and red valve, then shut down the vacuum pump. At this time, the pressure leak test mode can be used to check for leakage in the system. (Please refer to 6-3. Pressure Leak Test).

6-3. Pressure Leak Test

A. The instrument is powered on with the blue and red valves turned off.

B. Press the Mode button to enter the pressure leak test mode. The current pressure value is displayed at the lower right corner of the LCD.

LCD display showing: hh:mm 00:00, ΔP 0 kPa, 0 kPa, 600 kPa.

C. Press the Run/Stop button to start the leak test.

LCD display showing: hh:mm 00:45 •, ΔP 111 kPa, 600 kPa, 499 kPa.

At this time, the lower left corner records the initial pressure value; the lower right corner shows the instantaneous pressure value; the "ΔP" display area shows the difference between the initial and instantaneous pressure values.

The time display area shows how long the leak test lasts in the format of Hour: Minute (HH:MM). All pressure units on the screen are the same. You can switch different pressure units by pressing the Unit button.

7. Common Problems

7-1. Low Battery Power Supply

The instrument displays a low power sign when the battery is insufficient. The battery should be replaced as required to avoid affecting normal use.

7-2. Damaged Refrigerant Hose or Valve Stem

Please check the pipe fittings and hoses before testing. If any damage is found, replace them immediately to avoid improper use or accidents.

7-3. Failure of Refrigerant Filling

There is a valve core in the refrigerant inlet of the refrigeration system. When connecting the instrument, pay attention to the two terminals of the hoses. Connect one terminal with a core to the refrigeration system, while the other terminal without a core connects to the instrument.

7-4. Potential Leak Points

• Every hose terminal comes with a nylon pad that has a limited lifespan. Overuse or other situations can make it defective, leading to leakage.
• The instrument's refrigerant inlet (the middle port of the instrument) has a port with a valve core, used to vent air from the hoses after connecting the refrigerant to the instrument.

The port is equipped with a copper plug screw and requires tightening before or after each operation.

Check the refrigeration system's pipes and connectors.

8. Glossary

Saturation

The state of saturation is the coexistence of a refrigerant in a liquid and gas state.

Condensation Temperature and Evaporation Temperature

Condensation temperature: In the condenser, the refrigerant is condensed by the high-temperature gaseous refrigerant to the temperature of the liquid refrigerant, which is the saturation temperature under the condensing pressure.

Evaporation temperature: In the evaporator, the refrigerant evaporates from the liquid refrigerant to the temperature of the gaseous refrigerant, which is the saturation temperature under the evaporation pressure.

Degree of Subcooling and Superheat

Subcooling: Condensing temperature - condensing outlet temperature.

Superheat: Evaporation outlet temperature - evaporation temperature.

The degree of expansion of the expansion valve (refrigerant charge) affects the degree of superheat. The greater the degree of superheat, the smaller the opening of the expansion valve can be determined (indicating less refrigerant charge).

Lower subcooling can improve the refrigeration capacity of the system. Adding a subcooling circuit and economizer in the refrigeration system increases subcooling for refrigerant enhancement.

Sensible Heat and Latent Heat

The amount of heat required to raise the water temperature from 0 to 100 degrees is sensible heat. When water is heated to 100 degrees, it becomes water vapor, but the temperature remains at 100 degrees. The heat required for this process is called latent heat.

Gauge Pressure and Absolute Pressure

Gauge pressure: Refers to the pipeline pressure measured by pressure gauges, vacuum gauges, U-shaped tubes, etc. It is also known as relative pressure. The "table pressure" starts with atmospheric pressure, and the symbol is Pg.

Absolute pressure: The pressure directly acting on the surface of a container or object. Absolute pressure uses absolute vacuum as a starting point. The symbol is PABS (ABS is a subscript). Absolute pressure = atmospheric pressure + gauge pressure.

At atmospheric pressure, the gauge pressure is 0, and the absolute pressure is 1.013 bar.

Dry Bulb Temperature, Wet Bulb Temperature, and Black Ball Temperature

Dry bulb temperature: The temperature measured by ordinary thermometers.

Wet bulb temperature: A wet cloth is wrapped around the thermometer, and the temperature indicates a drop due to water evaporation. The temperature at this time is called the wet-bulb temperature.

The device, which includes both dry and wet bulb thermometers, is called a dry humidimeter and can be used to measure relative humidity in the atmosphere.

Black ball temperature: Also called actual temperature, it indicates the actual sensory temperature expressed by temperature when a person or object is combined with radiant heat and convective heat in a radiant heat environment. The black ball temperature measured is generally higher than the ambient temperature.

Relative Humidity and Absolute Humidity

Absolute humidity: The mass of water vapor in a unit volume of air. It represents the physical quantity of atmospheric dryness and humidity, usually expressed in grams of water vapor per cubic meter of air.

Relative humidity: The actual water vapor density in air compared to the percentage of saturated water vapor density at the same temperature.

The degree of dryness and humidity of the air is related to the degree of saturation of water vapor contained in the air, but not directly to the absolute amount of water vapor.

COP and EER

EER (Energy Efficiency Ratio): The ratio of cooling capacity to effective input power when the air conditioner performs a cooling operation under rated and specified conditions, expressed in W/W.

COP (Coefficient of Performance): Under rated operating conditions (high temperature) and specified conditions, for air-conditioning heat pump heating operation, it is the ratio of heating to effective input power, expressed in W/W.