Rheem-Ruud 42-42139-13 Contactor

Upgrade or restore your HVAC system with the Rheem-Ruud 42-42139-13 Contactor, a professional-grade 2-pole definite purpose contactor engineered for demanding air conditioning and heat pump applications. Featuring a 24V coil and a 40 amp FLA rating, this component is a drop-in replacement for numerous legacy parts including 42-25102-03 and 42-20617-01. Designed for reliable HVAC circuit control, it handles high-voltage electrical loads with a 240A locked rotor amp (LRA) capacity at 230V, making it suitable for 3.5 to 5-ton units. The double pole design ensures both legs of the power supply are interrupted, providing a safer and more complete disconnect than single-pole alternatives. Built to withstand high-cycle operations, this 40A contactor maintains low millivolt drop across the contacts to prevent overheating and premature pitting, ensuring consistent performance in high-surge environments.

Key Benefits

• Universal Mounting Compatibility: Features a standard mounting plate that aligns with most residential and commercial condenser unit configurations.
• High Amperage Capacity: Rated for 40 Amp FLA and up to 50 Amp resistive loads, providing ample headroom for heavy-duty compressors.
• Full Circuit Disconnect: The 2-pole mechanical interlock breaks both power legs for enhanced safety during the off-cycle.
• Sealed Contact Reliability: Engineered to minimize debris accumulation on the contact surfaces, reducing the risk of arcing and welding.
• Broad OEM Replacement: Directly replaces multiple Protech and Rheem-Ruud part numbers, ensuring a precise fit without field modifications.

Common Questions

Can I use a 40 amp contactor to replace a 30 amp contactor?
Yes, you can upgrade to a higher FLA (Full Load Amps) rating as long as the coil voltage (24V) and physical dimensions match. Increasing amperage capacity often improves component longevity under high-load conditions.

What is the difference between a 1.5-pole and this 2-pole contactor?
A 1.5-pole contactor has one switching pole and one permanent shunt (constant power), whereas this 2-pole contactor switches both power legs simultaneously, providing a complete electrical break for the compressor and fan.

Why is my contactor chattering or humming?
Chattering is typically caused by low voltage to the 24V coil (often due to a failing transformer or thermostat wiring) or debris trapped in the magnetic assembly. Use a multimeter to verify the control signal before replacing the component.

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.