Heil Quaker ICP 1008445 Limit Switch

When you're dealing with a furnace that is short-cycling or hitting a hard lockout, the Heil Quaker ICP 1008445 Limit Switch is the OEM replacement part required to restore circuit integrity. This is a normally closed (NC) disc-type switch specifically calibrated as a 190°F main limit switch with a 20°F differential. It serves as the primary safety mechanism for International Comfort Products (ICP) systems, ensuring the gas valve de-energizes if the heat exchanger temperatures exceed factory safety thresholds.

This genuine ICP 1008445 part is a direct replacement for HH680352 and is engineered for precise 1/2-inch disc mounting. It features an automatic reset function that closes the circuit once the plenum temperature drops to 170°F. For technicians servicing Heil, Tempstar, Comfortmaker, or Arcoaire units, this switch provides the exact thermal response curve required to prevent premature tripping while maintaining UL-certified safety standards.

Key Technical Benefits:

• Universal ICP Compatibility: Direct fit for a wide range of models including the C9MPD, H9MPV, and NTC6 series.
• Precise Thermal Calibration: Opens at 190°F and closes at 170°F, providing a consistent 20-degree differential for stable system operation.
• OEM Construction: High-grade disc housing and male spade connectors ensure a secure, low-resistance electrical connection.
• Critical Safety Compliance: Ensures the fan/limit control sequence operates within OEM specifications to prevent heat exchanger fatigue.

Common Service Questions:

What causes a 1008445 limit switch to trip frequently?
Frequent tripping is usually caused by restricted airflow. Check for a clogged furnace filter, internal evaporator coil blockages, or a failing blower motor. If the switch remains open even after the system has cooled, the internal disc may be fatigued, requiring a full replacement.

Can I use a universal limit switch instead of the 1008445?
While universal switches exist, they often lack the precise 190-20 temperature profile required for ICP furnaces. Using a non-spec switch can lead to unsafe operating conditions or nuisance shutdowns. Always use the original 1008445 OEM part to ensure the safety circuit matches the original design.

Is this the correct replacement for part HH680352?
Yes, 1008445 is the official superceding part number for HH680352. It is a drop-in replacement with identical mounting and thermal specifications.

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.