1. Introduction
This manual provides instructions for the proper use and handling of the Mastercool 92732 Universal UV Dye. This product is designed for leak detection in automotive and HVAC/R air conditioning systems. It is compatible with R-1234yf, hybrid, CO₂, and traditional refrigerants, as well as all common A/C lubricants including PAG, POE, ester, and mineral oils.
2. Safety Information
Always observe standard safety precautions when working with refrigerants and automotive systems. Wear appropriate personal protective equipment, including safety glasses and gloves, to prevent contact with skin and eyes. In case of contact, rinse thoroughly with water. Keep out of reach of children. Refer to the Safety Data Sheet (SDS) for complete safety information.
3. Product Features
- High Capacity: The 32 oz bottle provides up to 128 applications, suitable for extensive use in professional settings.
- Universal Compatibility: Formulated for use with R-1234yf, hybrid, CO₂, and traditional refrigerants.
- Bright UV Performance: Produces strong, visible fluorescence under UV light for effective leak detection.
- Versatile Formulation: Compatible with all common A/C lubricants, including PAG, POE, ester, and mineral oils.

Image 3.1: The Mastercool 92732 UV Dye 32 oz bottle, highlighting its high capacity for multiple applications.
4. Setup and Preparation
- Ensure the A/C system is depressurized or properly recovered before adding dye, unless using a dedicated dye injector designed for pressurized systems.
- Shake the Mastercool 92732 UV Dye bottle thoroughly before use to ensure uniform mixture.
- Determine the appropriate amount of dye needed based on the system's capacity. Refer to the application rates in the specifications section.
5. Operating Instructions: Dye Application and Leak Detection
5.1. Dye Injection
- For non-pressurized systems, add the measured amount of dye directly into the low-side service port or a suitable access point.
- For pressurized systems, use a compatible dye injector tool. Follow the injector manufacturer's instructions for safe and effective dye introduction.
- Once the dye is introduced, run the A/C system for at least 15-30 minutes to allow the dye to circulate thoroughly with the refrigerant and lubricant. This ensures the dye reaches all potential leak points.
5.2. Leak Detection
- After circulation, turn off the A/C system.
- Using a UV leak detection lamp (black light) and yellow-tinted glasses, inspect all components of the A/C system. Pay close attention to connections, hoses, seals, and compressor areas.
- A leak will appear as a bright, fluorescent yellow-green glow under the UV light.
- Mark any detected leak points for repair.

Image 5.1: Illustrates the use of a UV flashlight to identify fluorescent dye at a leak point in an A/C system.
6. Maintenance
Store the Mastercool 92732 UV Dye in its original container, tightly sealed, in a cool, dry place away from direct sunlight and extreme temperatures. Ensure the cap is securely fastened after each use to prevent contamination and evaporation.
7. Troubleshooting
- Dye not visible under UV light:
- Ensure the UV lamp is functioning correctly and is of sufficient intensity.
- Verify that yellow-tinted glasses are being used, as they enhance dye visibility.
- Allow more time for the dye to circulate within the system (run A/C for a longer duration).
- Check if enough dye was added for the system's capacity.
- False positives (dye visible where no leak exists):
- Clean the area thoroughly before inspection to remove any residual dye or contaminants from previous applications.
- Ensure the dye was injected cleanly without spillage.
8. Specifications
| Specification | Detail |
|---|---|
| Model Number | 92732 |
| Bottle Size | 32 oz (960 ml) |
| Applications | Up to 128 |
| Compatible Refrigerants | R-1234yf, R134a, R12, R22, CO₂, Hybrid Systems |
| Compatible Oils | PAG, POE, Ester, Mineral |
| Item Weight | 1 pound |
| Product Dimensions | 1.97 x 7.87 x 7.87 inches |
| UPC | 700376927320 |
| Manufacturer | Mastercool |
Application Rates:
- Automotive: 1 application per 10 oz (300 ml) lubricant.
- HVAC/R: 1 application per 7.5 oz (225 ml) or 7 lb (3.2 kg) refrigerant.

Image 8.1: Visual representation of the Mastercool 92732 UV Dye bottle alongside its technical specifications.
9. Warranty
This Mastercool product is covered by a Manufacturer Warranty. For specific details regarding warranty coverage, terms, and conditions, please refer to the documentation included with your purchase or contact Mastercool customer support.
10. Support
For technical assistance, product inquiries, or support, please contact Mastercool directly. Mastercool has over four decades of expertise and provides responsive U.S.-based technical support.
Visit the official Mastercool website for contact information and additional resources: www.mastercool.com





