Rcd hh18ha502 Auto Limit Switch 140-180F

Product Description

The RCD hh18ha502 is an auto-reset high-limit switch rated for a 140 to 180 degrees F operating range. High-limit switches are safety control components that monitor air or heat exchanger temperatures inside a furnace or air handler. When temperatures exceed the set threshold, the switch opens the control circuit and shuts down the burner or heating element, preventing overheating damage. Upon cooling to a safe temperature, the auto-reset design restores the circuit automatically without manual intervention. Licensed HVAC technicians install this switch as part of routine safety-control service or during a no-heat diagnostic on residential and light commercial forced-air heating systems.

The hh18ha502 is suited for forced-air furnace and air handler applications where a 140 to 180 degrees F auto-reset high-limit switch is required. It is identified as a Carrier parts and accessories component, making it a relevant replacement consideration for Carrier HVAC central air heating systems. Typical installation locations include the heat exchanger plenum area or supply-air plenum where the switch samples discharge air temperature to protect the equipment from thermal overload.

Key Features

• Auto-reset design restores circuit automatically after temperatures return to safe range, no manual reset required
• Operating temperature range of 140 to 180 degrees F provides reliable high-limit protection
• Functions as a high-limit safety switch to shut down burner or heating element on temperature overrun
• Direct-replacement style construction for Carrier HVAC forced-air heating equipment

Compatibility

Identified as a Carrier parts and accessories component for Carrier HVAC central air heating systems. For additional compatibility verification, cross-reference the hh18ha502 part number against the OEM service parts list for the specific furnace or air handler model being serviced.

Installation Notes

Installation should be performed by a licensed HVAC technician. Shut off all power to the furnace or air handler at the disconnect and confirm the system is de-energized before removing or installing any limit switch. Verify the replacement switch matches the original limit temperature rating and physical mounting configuration before completing the repair. Follow all applicable local codes and manufacturer service guidelines when performing safety-control replacements.

Technical Specifications

• Switch Type: High-Limit, Auto-Reset
• Temperature Range: 140 to 180 degrees F

Standard Information

• Brand: RCD
• Manufacturer Part Number: hh18ha502