Testo 552i App-Controlled Wireless Vacuum Probe

The Testo 552i is an app-controlled wireless vacuum probe designed for HVAC/R techs. It makes getting accurate vacuum readings on refrigeration, AC, and heat pump systems a breeze, all without losing any refrigerant.

Working on a busy rooftop or in a cramped plant room, having one less hose to wrangle just makes the job cleaner and faster, letting you focus on the evacuation itself.

Best For

• Refrigeration and AC Technicians
• Heat Pump Installers
• Service & Maintenance Teams
• HVAC Apprentices

Compatibility

This probe is built for evacuating refrigeration, air conditioning systems, and heat pumps. It connects via a standard 7/16" UNF fitting. Ensure your manifold or smart device supports Bluetooth 4.2 and has iOS 12.0+ or Android 6.0+ for app control. If you're running a different model, check fittings and specs before ordering.

Features

• Wireless vacuum measurement via Bluetooth, reducing hose clutter and refrigerant loss.
• App control with clear graphical display of vacuum progress and critical value alerts via smartphone vibration.
• Robust, easy-to-handle housing with IP54 protection class for dusty or damp job sites.
• Integrated 45° angle for simple and secure installation at any service port.
• Automatic connection to the Testo Smart App and compatible Testo digital manifolds (e.g., testo 557s, 550s).
• Reliable sensor technology that resists contamination, ensuring accurate readings without frequent cleaning.

Technical Specifications

What's in the Box

• testo 552i App-controlled wireless vacuum probe
• 3 x AAA batteries
• Calibration protocol

Using It on the Job

1. Ensure the refrigeration or AC system is fully depressurised and any necessary recovery procedures are complete before connecting the probe.
2. Attach the 552i probe directly to a service port, utilising the integrated 45° angle for convenient access. Hand-tighten the fitting for a secure, leak-free connection.
3. Power on the probe and open the Testo Smart App on your mobile device, or power on your compatible Testo digital manifold (e.g., testo 557s, 550s). The probe will connect automatically via Bluetooth.
4. Start your vacuum pump and monitor the evacuation progress on the app's graphic display or your manifold. Configure the app to alert you to critical vacuum values.
5. Once the target vacuum (e.g., 500 microns) is achieved and held stable, isolate the vacuum pump and monitor the system for any signs of vacuum decay over a set period.
6. After use, carefully disconnect the probe and store it in a clean, dry environment to maintain its accuracy and longevity.

Limitations & Safety Notes

• Refrigerant work, including system evacuation, requires a current ARCtick licence in Australia.
• Only for use on depressurised systems; do not connect to systems under high pressure.
• Ensure the correct fitting size (7/16" UNF) is used to avoid leaks, damage to the probe, or system contamination.
• Always follow Australian standards and Safe Work guidance for all system evacuation procedures.
• Keep the probe clean, especially the sensor, to ensure consistent and accurate readings.

Before you pull out the vacuum pump, always make sure your core depressors are in good nick. A leaky core will have you chasing your tail for hours, blaming the pump or the gauge. Check 'em first, save yourself the headache.

Pair With

Pair with Testo digital manifold gauges, a quality two-stage vacuum pump, and a set of core removal tools for comprehensive system evacuation.