Testo 549i Smartphone High-Pressure Meter

A. Product Overview

The Testo 549i is a professional high-pressure measuring instrument from the Testo Smart Probes series. It is designed for the installation, servicing, commissioning and troubleshooting of refrigeration and air-conditioning systems.

The instrument does not have a conventional built-in measurement display. Instead, it connects wirelessly to a compatible smartphone or tablet through the Testo Smart App. The mobile device acts as the display and operating interface.

The Testo 549i can be attached directly to the pressure connection using its 7/16 inch UNF connector. Its 45-degree angled connection makes installation easier, especially in restricted equipment spaces.

Because the instrument is used without conventional measuring hoses, refrigerant loss is eliminated or reduced to a very small quantity. This makes the Testo 549i practical for modern HVAC and refrigeration servicing.

Main Features

• Measures high and low pressure
• Measuring range from minus 1 to 60 bar
• Pressure resolution of 0.01 bar
• Accuracy of 0.5 percent of full-scale value
• Relative overload capacity up to 65 bar
• Direct hoseless connection to the system
• 7/16 inch UNF pressure connection
• 45-degree angled connector for easier installation
• Bluetooth range up to 100 metres
• Operates through the Testo Smart App
• Automatic calculation of evaporation temperature
• Automatic calculation of condensation temperature
• Graphical and tabular measurement display
• PDF and Excel report generation
• Approximately 130 hours of battery life
• Suitable for common refrigeration media

B. Working Principle

The Testo 549i works by connecting directly to the service or pressure port of an air-conditioning, refrigeration or heat-pump system.

Once connected, the internal pressure sensor detects the refrigerant pressure and converts it into a digital measurement signal. This measurement is transmitted through Bluetooth to the Testo Smart App installed on a smartphone or tablet.

The Testo Smart App displays the live pressure reading and uses the selected refrigerant data to calculate important system values, including:

• Evaporation temperature
• Condensation temperature
• High-side pressure
• Low-side pressure
• Measurement trends over time

For more detailed refrigeration analysis, the Testo 549i can be used simultaneously with the Testo 115i clamp thermometer. Combining pressure and pipe-temperature measurements allows the user to calculate parameters such as superheating.

Measurement readings can be presented as a graph or table. The user can also create reports, add customer information, photographs and comments, and export the results as PDF or Excel files.

C. Why It Is Used

Refrigeration System Pressure Measurement

The Testo 549i is used to measure refrigerant pressure during the installation, servicing and maintenance of refrigeration systems.

Air-Conditioning Troubleshooting

Incorrect system pressure can indicate low refrigerant charge, excessive refrigerant, restrictions, compressor problems or heat-exchanger performance issues. The Testo 549i helps technicians identify abnormal operating conditions.

High-Side and Low-Side Pressure Testing

Technicians can use separate Testo 549i probes on the high-pressure and low-pressure sides of a refrigeration system. The readings can be viewed simultaneously in the Testo Smart App.

Reduced Refrigerant Loss

Traditional manifold systems require measurement hoses that can retain or release refrigerant during connection and disconnection. The Testo 549i connects directly to the pressure port, reducing refrigerant loss during testing.

Evaporation and Condensation Temperature Calculation

The Testo Smart App automatically calculates the corresponding evaporation and condensation temperatures based on the measured pressure and selected refrigerant.

Measurement at Distant Pressure Points

The Bluetooth range of up to 100 metres makes it easier to measure pressure at points located far apart. The technician can view both readings from one smartphone or tablet.

Digital Service Documentation

The Testo 549i allows technicians to document system pressure readings and create professional digital reports. This is useful for commissioning records, maintenance reports and customer service documentation.

D. Suitable Buyers

The Testo 549i Smartphone High-Pressure Meter is suitable for:

• HVAC service technicians
• Air-conditioning installation companies
• Refrigeration service engineers
• Heat-pump technicians
• Cold-room maintenance companies
• Chiller service professionals
• Commercial refrigeration contractors
• Industrial maintenance departments
• Facility management companies
• Refrigeration equipment manufacturers
• Air-conditioning commissioning engineers
• Appliance repair technicians
• Technical training institutes
• HVAC tool dealers and distributors
• Refrigeration system consultants

It is particularly useful for technicians who require portable, wireless and low-loss pressure measurement during field servicing.

Technical Specifications

Frequently Asked Questions

1. What is the Testo 549i used for?

The Testo 549i is used to measure high and low pressure in refrigeration, air-conditioning and heat-pump systems during installation, servicing and troubleshooting.

2. What is the measuring range of the Testo 549i?

The Testo 549i has a measuring range from minus 1 to 60 bar.

3. Does the Testo 549i have a display?

No. The instrument uses a compatible smartphone or tablet as its display through the Testo Smart App.

4. How does the Testo 549i connect to a smartphone?

It connects wirelessly through Bluetooth. The stated Bluetooth range is up to 100 metres under suitable conditions.

5. Does the Testo 549i require measurement hoses?

No. It can be connected directly to the pressure port. This hoseless design helps minimise refrigerant loss.

6. What type of pressure connection does it use?

The Testo 549i uses a 7/16 inch UNF pressure connection.

7. Can it measure both high-side and low-side pressure?

Yes. A Testo 549i probe can be connected to either the high-pressure or low-pressure side. Two probes can be used to monitor both sides simultaneously.

8. Can the Testo 549i calculate evaporation temperature?

Yes. The Testo Smart App automatically calculates evaporation temperature using the measured pressure and selected refrigerant.

9. Can it calculate condensation temperature?

Yes. The Testo Smart App can calculate the corresponding condensation temperature from the measured pressure.

10. Can the Testo 549i measure superheating?

The Testo 549i can be used with the Testo 115i clamp thermometer to calculate refrigeration parameters such as superheating.

11. Can measurement data be displayed as a graph?

Yes. Measurement values can be displayed in graphical or tabular form through the Testo Smart App.

12. Can the instrument generate reports?

Yes. The app can generate measurement reports containing readings, photographs and comments. Reports can be exported in PDF or Excel format.

13. What is the overload capacity of the Testo 549i?

The specified relative overload capacity is 65 bar.

14. How long does the battery last?

The stated battery life is approximately 130 hours.

15. What is included with the Testo 549i?

The standard product package includes the Testo 549i high-pressure measuring instrument, batteries and a calibration protocol.

16. Is the Testo 549i suitable for heat-pump servicing?

Yes. It is suitable for pressure measurement during the installation, commissioning and servicing of compatible heat-pump systems.

17. Which refrigerant media can be measured?

The datasheet lists compatibility with CFC, HFC and HCFC refrigerants, as well as nitrogen, water and carbon dioxide.

18. Is the Testo 549i suitable for professional HVAC technicians?

Yes. Its compact construction, direct connection, long Bluetooth range and app-based analysis make it suitable for professional HVAC and refrigeration service work.