Lennox 36A77 Relay

The Lennox 36A77 Relay is a mission-critical 24V 3PDT relay engineered for precise electrical switching in commercial and residential HVAC systems. Also recognized by part number 36A7701 and manufacturing number P-8-11112, this DPDT/3PDT general-purpose relay is a standard replacement for many Lennox GCS and GHP series units. When you are dealing with a blower motor that won't kick on or a control circuit failing to close, this OEM Lennox replacement part provides the exact coil impedance and contact rating required to prevent secondary transformer stress or circuit board faults. The Lennox 36A77 ensures reliable pilot duty and power switching, maintaining the integrity of the original factory sequence of operation. Its compact footprint allows for seamless mounting in tight control cabinets, making it a staple for any technician's van stock when servicing Lennox rooftop units or split systems.

• Direct OEM Compatibility: Functionally identical to the 36A7701, ensuring a drop-in fit without rewiring or bracket modification.
• Versatile 3PDT Configuration: Provides multi-pole switching capability for complex control voltage logic and simultaneous component activation.
• Industrial-Grade Contacts: Designed to handle the inductive loads of HVAC blower motors and condenser fan relays without premature pitting or sticking.
• System Protection: Matches factory electrical specs to avoid pulling excessive amperage from the 24V transformer.

• Is the 36A77 interchangeable with the 36A7701? Yes, the 36A7701 is the updated part number for the 36A77; they are technically identical and fully interchangeable in all Lennox HVAC applications.
• What are the symptoms of a failing 36A77 relay? Common signs include a "clicking" sound without motor engagement, 24V present at the coil but no continuity across the normally open (NO) contacts, or visible scorching at the terminals.
• Can I use this relay for high-voltage switching? While the coil is 24VAC, the contacts are rated for standard line voltage applications typical in Lennox control circuits; always verify the amp draw on the motor nameplate against the relay's contact rating.

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.