ensuring the furnace high limit prevents heat exchanger overheating

If your voltmeter shows 24V entering the switch but 0V leaving while the inducer is at full speed

and various RBM-style Type 184 relays

Always use the included gasket for NPS connections

Trane THT2243 Thermostat ensuring the furnace high limitThe Trane THT2243 Thermostat is a heavy duty 240V SPST thermostat specifically engineered as a limit control and temperature regulator for commercial and residential condenser units. Operating as a single pole, single throw (SPST) switch, this component is designed for 105Op73Cl operation, meaning it triggers an open circuit at 105F and restores the connection when temperatures drop to 73F. Professional technicians rely on this OEM replacement part