OEM Lennox Transformer — 46W11

The genuine OEM Lennox 46W11 transformer steps line-voltage power down to the low-voltage current that runs your Lennox control circuit. It supplies stable 24V power to the thermostat, control board, relays, and contactor coils — the signals that tell your system when to call for heating or cooling. Built to Lennox specifications, the 46W11 provides the correct primary and secondary voltage and VA rating your unit was engineered around.

A failed transformer usually takes the whole control circuit down with it. Common symptoms include a dead or unresponsive thermostat, a system that won't start a heating or cooling cycle, contactors and relays that won't pull in, repeatedly blown low-voltage fuses, or a scorched, buzzing, or burnt-smelling transformer. These point to shorted windings or overload on the secondary side.

OEM matters here because control voltage must be precise. An undersized or off-spec transformer can leave contactor coils under-energized and cause erratic, hard-to-diagnose faults across the system. The Lennox 46W11 is manufactured and tested to deliver clean, correctly rated power, protecting your control board and preserving warranty coverage. In stock and ready to ship same day before 3PM CST.