York Heartbeat

What does York Heartbeat mean?

A steady, repeating heartbeat blink on the gas-heat ignition control board (ICB) is the all-clear status. It confirms the board has power, has passed its self-check, and that every function needed to respond to a call for heat is available. No fault or error information is being displayed; the furnace is operating normally or waiting for the thermostat to call for heat.

Symptoms

• ICB LED pulses in a slow, even heartbeat pattern
• Furnace heats normally when the thermostat calls for heat
• No lockout, no flame or pressure faults are present
• Burners light and the blower cycles as expected

Common causes

• The control board is powered and has passed self-check
• All monitored safety inputs are in their expected state
• There is no active heating demand or the unit is heating normally

Diagnostic steps

1. 01

   Confirm the heartbeat pattern

   Verify the LED is blinking in a steady, even rhythm rather than a counted burst of flashes, which would indicate a fault.

2. 02

   Check the call for heat

   Set the thermostat above room temperature and confirm the furnace responds with a normal ignition sequence.

3. 03

   Observe a full heat cycle

   Watch the inducer start, ignition occur, and the blower energize to confirm normal end-to-end operation.

4. 04

   Leave the unit in service

   No corrective action is required for a heartbeat code; it indicates the control is healthy.

When to call a professional

A heartbeat code requires no service. If the furnace is not heating even though the board shows a steady heartbeat, the issue lies outside the ignition control — for example the thermostat, low-voltage wiring, or the unit control board. If you cannot get a normal heat cycle to start, contact a licensed HVAC technician to trace the call-for-heat signal back to its source.