CAT Electronic Rust Protection — For Air Conditioners
The CATIII System delivers a low-voltage electronic field across the metallic structure of the air-conditioning unit, slowing down corrosion on both external surfaces and internal components. Designed for coastal homes, marine environments, high-rise balconies, mining camps and commercial sites where standard coatings deteriorate quickly.

Technical & Design Summary
The CAT System utilises an optimal blend of voltage and frequency to deliver maximum corrosion inhibition in air conditioner systems. The Modular Design allows for easy expansion, with the Main Generator Module featuring 2 output circuits. Each circuit can support up to 6 coupler pads linked in series, providing a total capacity of 12 Coupler Pads for both circuits. Additional coupler pads can be seamlessly added to enhance system performance.
Why Choose CAT for your Air Conditioner
While traditional methods of corrosion control, such as coatings, are effective for certain applications, they may not fully address the unique challenges faced by air conditioner systems. The CAT System pioneers a different approach by employing alternating current (AC) with specific waveforms and frequencies to interrupt and slow down the corrosion process within the metallic components of air conditioner units. This technology has been refined since its inception in 1989, demonstrating its effectiveness even in real-world conditions. While the exact mechanisms behind its efficacy are still debated, it is widely believed that the CAT technology helps regulate stray currents within the system, thereby mitigating corrosion.
Comprehensive Coverage
CAT reaches virtually all metallic surfaces, both internal and external, offering consistent protection even in hard-to-reach areas where coatings often fall short. It ensures a better defence against corrosion risks.
Long-term Solution
Unlike traditional coatings that fade or peel over time, CAT provides continuous, long-lasting protection. Once installed, it delivers ongoing corrosion suppression without the need for reapplication.
Continuous Protection
The system operates silently 24/7, providing round-the-clock corrosion defence. It ensures your air-conditioning unit is always protected, no matter the season or environmental conditions.
Environmentally Friendly
CAT is fully compatible with air-conditioning control systems and electronics. It operates independently without disrupting any onboard circuits, diagnostics, or automated functions.
Non-Interference
Unlike traditional coatings that fade or peel over time, CAT provides continuous, long-lasting protection. Once installed, it delivers ongoing corrosion suppression without the need for reapplication.
Easy Installation
The system is designed for fast, hassle-free installation with no drilling or structural changes required. It can be fitted to new or existing units in minutes using standard tools.
Technical Specifications
System Capabilities
- Compatible with both 12VDC and 24VDC systems
- Option for 240VAC conversion available
- Modular design for easy expansion
- Main Generator Module with 2 output circuits
- Supports up to 12 Coupler Pads (6 per circuit)
- Additional coupler pads can be added as needed
Paint Protection Bonus
Anecdotally we have found the CAT slows down paint oxidation, further preserving the integrity of air conditioner units.

Aircon FAQs
Q: What is electronic rust prevention?
A: Electronic rust prevention utilizes electricity to mitigate corrosion on metal surfaces. CAT employs this technology that can protect air conditioner units from rust and degradation.
Q: How does CAT work?
A: CAT disrupts the natural electrochemical rusting process within air conditioner systems, providing continuous corrosion protection.
Q: Is CAT protection expensive?
A: No. The cost of CAT installation represents a small fraction of the value of air conditioner units, offering long-term savings by preventing costly corrosion-related repairs.
Q: Does CAT come with a warranty or guarantee?
A: Yes. All CAT Systems are backed by a 10-year product replacement guarantee, subject to terms and conditions.
Q: What voltage is needed to power the CAT system?
A: The CAT system requires either a 12VDC or 24VDC constant voltage source. For 240VAC installations, a power transformer will be necessary. (a 12VDC domestic down light transformer is ideal for this purpose.)
Q: Is CAT effective on larger air conditioner units?
A: Yes. CAT’s modular design allows for scalability, making it suitable for various sizes of air conditioner units.
Q: Is it practical to install CAT on air conditioner units with existing rust?
A: While CAT can help mitigate further corrosion, it cannot reverse existing rust damage. It’s recommended to address existing rust issues before installing CAT for optimal protection.
Q: Will CAT interfere with the operation of air conditioner units?
A: No, CAT does not interfere with the operation of air conditioner units. It operates independently and seamlessly integrates with the existing system without affecting its performance.
Q: Is CAT compatible with existing protective coatings?
A: Yes. CAT is fully compatible with various protective coatings, enhancing corrosion resistance when used in conjunction with suitable coatings.
This is what our customers say….
“During the last 6 years or so we have installed well over 100 CAT SYSTEM electronic rust control units on the high rise outside air-conditioners. These air-conditioners are exposed to salt air 24 hours a day. In all that time there has been only one failure, the air-conditioner rusted because CAT SYSTEM connection was not switched on!
CAT Systems Australia are most professional to deal with, providing excellent service and marketing a high-quality unit with a most satisfactory performance result. I have no hesitation in recommendingg CAT SYSTEMS for complete rust protection.”
Brian Doyle – 4/11/2013, L&M Electronics Pty Ltd