The Trane 4349806 Limit Switch/Thermostat is a genuine OEM safety component designed to protect HVAC systems from overheating. This switch opens at 190F to interrupt operation and automatically resets once temperatures return to safe levels. It includes the factory-installed mounting bracket for direct, secure installation. If your unit is shutting down prematurely, failing to start, or showing high-temperature faults, this OEM limit switch is the correct replacement. Key Features Genuine Trane OEM limit switch / high-limit thermostat 190F trip temperature, auto-reset, normally closed Includes factory mounting bracket for quick installation Prevents overheating and protects heat exchangers and components Ensures safe and reliable system operation Fixes common issues: overheating lockouts, blower running constantly, heater not cycling Specifications Part Number: 4349806 Type: High-Limit Switch / Thermostat Temperature Rating: 190F Operation: Normally Closed, Auto Reset Mounting: Pre-installed bracket Application: Trane commercial rooftop split systems Compatible Models (Shortened List) Fits popular models such as: YHC072A3EHA0500A0C1000600 YHC072A3EHA05000000000000 YHC072A3EHA0000 ?and 2,600+ additional Trane units. Why Choose This Item This is the exact OEM limit switch specified by Trane for commercial HVAC systems. It guarantees proper temperature protection, system reliability, and the correct cutout/reset performance?unlike generic alternatives that may cause nuisance trips or improper cycling.