Rcd hh18ha507 Auto Limit Switch 145-185F

Product Description

The RCD hh18ha507 is an auto-reset high-limit switch rated for a temperature range of 145 to 185 degrees F. It monitors supply air or heat exchanger temperatures inside a forced-air furnace, opening the circuit when temperatures exceed the set threshold and automatically resetting once conditions return to a safe level. Licensed HVAC technicians install this switch as part of routine furnace service or component-level repair. Its auto-reset design means the system can resume normal operation without manual intervention once the overheat condition clears.

This limit switch is suited for residential forced-air gas furnace applications where automatic temperature protection is required. It is designed to interrupt control-circuit voltage when the monitored surface or air temperature climbs beyond the rated limit, protecting the heat exchanger and blower components from sustained overheat conditions. The 145 to 185 degrees F operating range covers common residential furnace high-limit requirements.

Key Features

• Auto-reset operation — no manual reset required after the overheat condition clears
• Temperature range of 145 to 185 degrees F suits typical residential furnace high-limit applications
• Functions as a high-limit switch to interrupt the control circuit and prevent heat exchanger damage
• Direct replacement form factor for compatible furnace control circuits

Compatibility

Designed as an OEM-style replacement high-limit switch for residential forced-air gas furnace control systems requiring a 145 to 185 degrees F auto-reset limit switch.

Installation Notes

Installation should be performed by a licensed HVAC technician. Disconnect power to the furnace at the disconnect switch or breaker and shut off the gas supply before removing or installing any limit switch. Confirm the replacement switch matches the original mounting configuration and control-circuit wiring before restoring power. Always verify proper system operation and check for recurring overheat fault conditions after installation.

Technical Specifications

• Temperature Range: 145 to 185 degrees F
• Reset Type: Auto Reset
• Switch Type: High Limit

Standard Information

• Brand: RCD
• Manufacturer Part Number: hh18ha507