Lennox Y8844 Supco Q103 electric heat sequencer is a field-proven HVAC control designed to manage the staged operation of electric heating elements and blower motors in electric, gas, or oil heating systems. This reliable replacement sequencer helps ensure proper start-up and shutdown timing, improving system safety, efficiency, and overall performance.

The Q103 sequencer features two internal switches with controlled on and off timing to prevent electrical surges and overheating. Contacts M1–M2 energize first and disengage last, allowing smooth heat staging and coordinated blower operation. A built-in delay between stages supports consistent airflow and dependable system control across a wide range of applications.

UL and CSA approved, this sequencer operates on a standard 24-volt control circuit and is suitable for residential and light commercial HVAC systems. Ideal for service replacements or system repairs, the Supco Q103 offers dependable operation backed by a one-year warranty.