Goodman B1256559 Heat Sequencer – Genuine OEM 24V 2-Stage Staging Relay

The Goodman B1256559 Heat Sequencer is a critical mechanical timing component designed to regulate the sequential activation of electric heating elements in your HVAC system. Often described as the "timing center" for electric heat, this genuine OEM part ensures that heating coils energize and de-energize in a specific, staggered order. This function is vital for protecting your home’s electrical panel from massive current surges that occur when multiple 5kW elements pull power simultaneously. Engineered for Goodman, Amana, and Janitrol furnace and air handler series, the B1256559 provides the precise thermal delay needed to ensure the blower motor is moving air before the elements reach peak temperature, preventing the high-limit safety switches from tripping.

Key Features and Function:

• Precision Airflow Management: Expertly orchestrates the turn-on/turn-off sequence of heating elements to provide consistent discharge air temperatures.
• Genuine OEM Reliability/Fitment: Manufactured to original factory specifications, guaranteeing the exact "On" and "Off" delay timings required by your specific furnace series.
• Electrical Surge Protection: Prevents detrimental power spikes by maintaining a systematic activation delay, protecting both the HVAC equipment and your home's circuit breakers.
• Heavy-Duty Bimetal Design: Utilizes a rugged internal thermal disc to manage high-amperage resistive loads without the "chattering" or hum common in universal relays.

Product Details and Key Specifications:

• Part Number: B1256559 (Replaces B1256552, B12565-52, B12565-59)
• Manufacturer: Goodman / Amana (Genuine OEM)
• Part Type: 2-Stage Heat Sequencer Relay
• Voltage: 24 VAC (Control Circuit)
• Amperage: 30 Amps @ 240V
• Timing: On: 1 to 20 Seconds | Off: 40 to 110 Seconds
• Number of Stacks/Switches: 2-High Stack (M1-M2, M3-M4)
• Dimensions: 4 in x 23.75 in x 30.75 in (Packaged)
• Shipping Weight: 0.3 lbs

🛠️ HVAC Depot Pro Tip: The Terminal Verification

When replacing the B1256559, always verify the wiring against the original unit's terminal markings. These sequencers use a 24V heater coil at the base to warp a bimetal disc; if you accidentally swap the 24V control wires with the 240V load wires, you will instantly destroy the sequencer and potentially the furnace transformer. During your Diagnostic Check, if the heating elements stay on after the thermostat is satisfied, the contacts have likely welded shut. Always use "Take a Picture First" before removing any of the 1/4" quick-connect terminals.

Cross-Reference & Compatibility:

The B1256559 is a direct OEM replacement for the following part numbers:

• OEM Numbers: B1256552, B12565-52, B1256559S, 0130M00063
• Therm-O-Disc: 15S22, 15S21, 309837, H1-20 C40-110
• Aftermarket Cross: Emerson 24A34-3, Mars 31259, Packard SEQ6002, Klixon 60000E02-3

Extensive Model Compatibility List:

Note: Use 'CTRL+F' to search for your specific model:

• Goodman Air Handlers: AWUF180516, AWUF240516, AWUF300516, AWUF301016, AWUF360816, ARUF1824, ARUF3030, ARUF3642
• Goodman Heater Kits: HKR-05, HKR-08, HKR-10, HKR-15C, HKR-20C, HKSC15, HKSC20
• Amana Units: ASPT, ASUF, and AMVE series electric heat sections.
• Legacy Series: Fits various Janitrol, Kenmore, and GMC electric furnace models requiring 2-stage staging.