AO Smith 310 series condensing tankless error code 61
Induced draft fan fault
Which models this applies to. This page covers the AO Smith 310 series condensing tankless gas water heater codes.
What is specific to the 310 series condensing tankless platform
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.
Your control board prints the code as text, for example F01 or EE3, so you read it off the display rather than counting blinks. The printed number is the fault itself, not a position in a table.
Quick answer
On AO Smith 310 series condensing tankless, 61 is a fault. It means induced draft fan fault. A first thing to check: Dust and lint packed into the fan wheel and housing.
- Applies to
- AO Smith 310 series condensing tankless
- AO Smith 310 series condensing tankless gas water heater codes · Water Heater
- Type of code
- Fault
- Urgency: Needs attention soon
- First safe check
- With the unit off and cool, look through the intake or the burner compartment at the fan wheel and note any visible mat of dust and lint.
What 61 means on this model
A condensing unit pulls its combustion gases through the heat exchanger with a fan and the control verifies the fan is turning. This code means it is not getting a believable signal, or the fan is not moving enough air, and the unit will stop on it.
Symptoms you will notice
- Code appears at startup, sometimes after a delay
- Fan is silent when it should be running
- Fan runs but the unit still reports the fault
- Unit shuts down on a heat demand and will not stay in
- You can hear the fan spinning but the flame will not hold
Common causes
The code tells you what the control detected, not which part failed. These are the causes we see most often, roughly in order of likelihood:
- Dust and lint packed into the fan wheel and housing
- Frozen or corroded connector at the fan motor
- Failed fan motor or a seized bearing
- Broken wiring between the fan and the board
- Burn marks on the board at the fan connector
What you can safely check
These are homeowner-level checks. None of them need you to open a live electrical compartment or work on gas.
- With the unit off and cool, look through the intake or the burner compartment at the fan wheel and note any visible mat of dust and lint.
- Cycle the power and listen at the transition. A fan that starts, runs, and stops with the burner is normal purge behaviour and is not a fault by itself.
- With power off, inspect the fan connector for corrosion, a pushed-back pin, or a latch that has backed off.
- Confirm the fan wheel turns freely by hand with the unit off. It should spin smoothly with no scraping.
Do not do these
- ×Do not run the unit with the fan disconnected to see whether the code clears. The fan is part of the combustion air proving.
- ×Do not use compressed air to blow dust out of the fan wheel in a way that sends it into the heat exchanger or the burner ports.
- ×Do not lubricate the fan motor. Replacement is the fix, not servicing.
When to call a technician
Book a technician, do not keep resetting it
This fault will not clear on its own. Every power cycle gives the control one more failed attempt, and repeated attempts are what turn a cheap part replacement into a seized or contaminated system.
- This is a fuel-burning appliance, so treat anything involving a burner, gas valve or flue as technician work. If you smell gas at any point, leave the property and call the gas utility from outside rather than continuing to diagnose.
- If the appliance has stopped mid-cycle, is making a noise you have not heard before, or smells burnt, stop reading here and call. Those are symptoms of something the fault code does not describe well enough.
Cleaning lint off a fan wheel is reasonable if you can reach it without pulling the appliance apart. The motor and its wiring are a technician job.
What it costs to fix
Parts
Induced draft fan motor $180 to $400. Fan connector and harness $40 to $120.
Labor
Two to three hours to reach, clean, or replace the fan on a condensing unit.
DIY or technician
Cleaning lint off a fan wheel is reasonable if you can reach it without pulling the appliance apart. The motor and its wiring are a technician job.
Typical US part and labor ranges, 2026. They vary by region, model and contractor, so treat them as a planning figure, not a quote.
Scope of this code
- Code table
- AO Smith 310 series condensing tankless gas water heater codes
- How this model reports the code
- Printed on the control display
- Models in scope
- AO Smith 310 series condensing tankless
- How this platform differs
- 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.
- Checked
- Confirm on your own unit
- Find the model number on the data plate, then check this code in the service manual for that model. Manufacturers revise code tables between model years, and a revised board can renumber a fault.