HVAC Code Lookup

York Furnace: 7 Flashes

A York furnace LED pattern starting with 7 flashes matches 2 documented codes: 7 red flashes, 7 red flashes (YP9C modulating). Watch the full pattern (short vs. long flashes) to tell them apart — all 2 are explained below.

Code 7 red flashes: The burners failed to light on three trials for ignition, so the control locks out for one hour and then tries again

Soft lockoutShown as: Seven red flashes, then a two-second pause, repeating

The burners failed to light on three trials for ignition, so the control locks out for one hour and then tries again.

Manual wording: “7 RED FLASHES: This fault code indicates that the flame could not be established during three trials for ignition... The furnace will lock out for one hour and then restart.”

Documented for: TG8S, TG9S, TM9E, TM9X, TM8X, TM9T, TM8T, TM9V, TM8Y, TM9Y

Likely causes, most common first

  1. Gas valve switch left in the OFF position
  2. Low or no gas pressure
  3. Faulty gas valve
  4. Dirty or faulty flame sensor
  5. Faulty hot surface ignitor
  6. Loose wires or a burner problem

What you can safely check yourself

  • Check that other gas appliances in the house (stove, water heater) still work - if none do, the gas supply is out
  • Replace a dirty air filter
  • Check the outside vent and intake pipes for blockage
  • Cycle the furnace off and on once at the service switch to let it retry

When to call a technician

Anything past confirming you have gas to the house - ignitor, flame sensor, gas valve - is technician work in a live gas compartment.

A York furnace throwing this code repeatedly has a reason — clearing the code without fixing the cause just hides it.

Sources

Full page for York code 7 red flashes

Code 7 red flashes (YP9C modulating): Lockout due to no ignition

Soft lockoutShown as: Seven red flashes, two-second pause, repeating

Lockout due to no ignition. The control tried three times to light the burners and failed, so it locks out for one hour and then tries again.

Manual wording: “Seven Red Flashes - Lockout due to no ignition. The control will try three times for ignition. If flame cannot be established in three tries, the control will lockout for one hour and then will try again to light.”

Documented for: YP9C, YPLC modulating furnaces

Likely causes, most common first

  1. No or low gas supply
  2. Failed hot surface ignitor
  3. Faulty gas valve
  4. Dirty or faulty flame sensor

What you can safely check yourself

  • Check that other gas appliances in the house still work
  • Replace a dirty air filter
  • Check the outside vent and intake pipes for blockage
  • Cycle the furnace off and on once at the service switch to let it retry

When to call a technician

Ignitor, flame sensor and gas valve work all happen inside the live gas compartment. Call a technician.

A York furnace throwing this code repeatedly has a reason — clearing the code without fixing the cause just hides it.

Source

Full page for York code 7 red flashes (YP9C modulating)

Other York codes