Lennox 45A00 Potential Relay

The Lennox 45A00 Potential Relay is a mission-critical component engineered to manage high-voltage induction motor startup in residential and commercial HVAC units. As a high-performance HVAC startup relay, it utilizes a precisely calibrated coil sensitive to back EMF to disengage the start capacitor once the compressor reaches approximately 75% to 80% of its rated synchronous speed. Built for longevity in demanding environments, this 45A00 potential relay features a rugged construction with a weight of 0.32 lbs and specialized electrical ratings, including a pickup voltage of 242-272V and a dropout voltage of 60-121V. This ensures the compressor start relay provides a clean break, preventing capacitor overheating and winding damage. With a continuous coil voltage rating of 420V and 35A capacity, it is a direct OEM Lennox replacement part for legacy and modern systems like the CHA15, CHP15, and HP16 series. For technicians servicing Lennox HVAC systems, this relay is the standard for maintaining reliable torque and efficient motor acceleration.

• Precise Voltage Cycling: Optimized 242-272V pickup range ensures start capacitors are engaged only when necessary for high-torque startup.
• Heavy-Duty Electrical Rating: 420V continuous voltage and 35A current capacity handle the inductive loads of robust commercial compressors.
• Direct OEM Compatibility: Engineered specifically for Lennox equipment, ensuring correct physical mounting and terminal alignment for faster field installations.
• Motor Protection: Prevents premature motor failure by ensuring the start circuit is de-energized immediately after the rotor reaches operational velocity.

What causes a potential relay like the 45A00 to fail?
Most failures stem from welded contacts due to excessive arcing or a weakened internal spring, which prevents the contacts from opening and risks burning out the start capacitor.

Can I use this relay for multiple horsepower ratings?
This relay is specified by its pickup, dropout, and continuous voltage ratings; always verify the back EMF of your specific compressor motor against the 242-272V pickup spec before installation.

How do I verify if the 45A00 is compatible with my Lennox unit?
Check the technical data plate on your unit. This part is a standard match for many Lennox HP and CH series models, but verifying the manufacturer part number is essential for exact fitment.

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Disclaimer: While we strive for 100% accuracy, product data and specifications are subject to change. Please contact our team to confirm compatibility or technical details before purchasing.