AO Smith · Water Heater
AO Smith 310 series condensing tankless error codes
AO Smith 310 series condensing tankless gas water heater codes. 12 codes.
Check this is your model before you read on
The model number on your data plate should start with 310. These are two-digit fault numbers, not a count of anything on the appliance. Where a number is also a legitimate reading, such as the burner hours or the gas type setting, it still only appears here as a fault when the control is reporting the fault rather than the setting.
Sealed combustion condensing unit available as direct vent, indoor and outdoor versions. The same two-digit fault numbers apply across the versions, and the fault appears on the control board LED and on the remote controller when one is fitted.
How to read this code
This unit reports faults as a two-digit number rather than a blinking light pattern, so you read the number first and then count the repeats. The code appears on the red LED on the control board inside the burner compartment, and on the remote controller if one is fitted. The repeat count is part of the code: 03 blinks once, 32 blinks twice, 11 blinks three times, 61 four times, 10 and 99 five times, and 55 and 72 six times. The number is what identifies the fault, the repeat count tells you how many attempts the control made before it gave up. Do not count the count on its own, because a unit with a display may just show the number.
12 codes on this control platform.
12 fault codes
Every one of these means something is wrong. Ordered by how urgent they are.