York 11 red flashes: The main limit switch has opened and stayed open for more than five

Source: York manual (PDF) (opens in a new tab) ↗ · Updated

Status code11 red flashesYork
What does York 11 red flashes mean?

The main limit switch has opened and stayed open for more than five minutes. The manual says this is usually a failed blower motor or blower wheel. The control is in a hard lockout. Power has to be cycled off and on only after the problem is corrected.

Call a pro: jump to when to call a pro Equipment type: furnace
How it shows: LED behind the blower-door view port on a York TG9S. Each flash is 1/3 second on and 1/3 second off, then a 2-second pause: 11 red flashes

York TG9S 11 red flashes means the main limit stayed open more than five minutes. The manual says that is usually a failed blower motor or blower wheel, and it is a hard lockout. Power is cycled only after the blower problem is corrected. It is the next step after 4 red flashes when the limit does not reclose. The dirty-filter check is on 4 red flashes, not on this hard lockout.

Likely causes

  • Failed blower motor
  • Failed blower wheel

Safe checks for 11 red flashes

  1. Turn the furnace off. Cycling the breaker before the blower problem is fixed only repeats the lockout
  2. This code follows the 4 red flash limit fault when the limit stays open for more than five minutes
  3. Techniciancheck the blower motor and the blower wheel
Safety firstIf you smell gas, do not touch any electrical switch or use a phone in the building; leave immediately and call your gas supplier from outside. Turn off electrical power at the furnace switch or breaker before opening any panel, and never bypass or jumper a limit, rollout or pressure switch. Gas valve, burner, venting, wiring and control-board work should be done by a licensed HVAC technician.

Capacitors can hold a charge after the power is off. Safety terms.

When to call a pro

Call a licensed HVAC technician. Eleven red flashes means the limit stayed open long enough that the control treats the blower as failed.

Email me this fix

We save your email and this page. Nothing is emailed. We'll only use your email for this request.

Privacy. Deletion requests go to the address on that page.

Request a filter and maintenance reminder

We save your email, this page, and the interval you pick. Nothing is emailed. We'll only use your email for this request.

Privacy. Deletion requests go to the address on that page.

Parts & tools for this fix

Taken from this code's causes or steps. A search link opens Amazon results and does not confirm a fit. Check the model number in the manual.

Furnace blower (circulator) motor: guide

In this code: Failed blower motor

This one is for a technician to test or replace, so we only explain it and do not link to buy it.

High limit and rollout switches: guide

In this code: This code follows the 4 red flash limit fault when the limit stays open for more than five minutes

A safety device: we explain it but do not link to buy one.

Related York codes

1 red flashFlame was sensed when there was10 red flashesThe gas valve is energized with2 red flashesThe pressure switch is closed when4 red flashesThe main limit switch has opened3 red flashesThe pressure switch contacts are open7 red flashesThe flame could not be established

All York codes →Browse every code