On the covered Carrier gas furnace, 11 means the control has no stored fault to report. Carrier explains that stored status codes are erased after 72 hours, or cleared by a technician, and that 11 is also what the control shows after a successful component test. When a technician replays stored codes, 11 marks the end of the list. First, run the furnace through one full heating cycle and watch the LED for up to 20 minutes, the observation window Carrier's start-up steps use.
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0 of 2 completedWhat to do first
ReversibleRun the furnace through one full heating cycle and watch the LED for up to 20 minutes, the observation window Carrier's start-up steps use.
Correct only the documented fault domain
ReversibleAn 11 on its own is not a fault. If the furnace is still not heating, check that the thermostat is set to Heat and calling, the blower door is fully seated, the filter is clean and the service switch is on. Carrier's guide says that if 11 keeps flashing after a technician has set the setup switches SW1-1 and SW1-6 to their normal positions, the furnace control is the part to replace.
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What does 11 mean on a Carrier gas furnace?+
The control has no stored fault to report. Carrier explains that stored status codes are erased after 72 hours, or cleared by a technician, and that 11 is also what the control shows after a successful component test. When a technician replays stored codes, 11 marks the end of the list.