Quick answer: Lennox code 201 (often shown as E201) means the furnace control board cannot communicate with the indoor blower motor. Without the blower, the furnace cannot safely heat, so it stops. The usual causes are a loose or damaged blower harness, a failed motor control module, or a control board problem.
Safety first: if you smell gas, do not reset or relight anything. Leave the home and call Nicor Gas at 1-888-642-6748 or 911 from outside.
What Does Lennox Error Code 201 Mean?
Lennox describes code 201 as an indoor blower communication failure: unable to communicate with blower motor. Many Lennox furnaces, including the SL280, EL280, EL297V and SLP99V, use a variable-speed (ECM) blower motor that talks to the furnace control over a data connection. When that conversation stops, the control logs code 201 and will not run a heat cycle, because heating without airflow would overheat the furnace.
You may see the code on the furnace control’s display, on a Lennox iComfort or ComfortSense thermostat, or in the Lennox app.
Common Causes of Code 201
- Loose or damaged wiring between the control board and blower motor, including the low-voltage communication harness and the power plug at the motor.
- Failed blower motor control module. The electronics on the back of an ECM motor can fail even when the motor itself is fine.
- A failed blower motor.
- Power surges or brownouts that disrupt the motor electronics.
- Water damage from a leaking AC coil, condensate trap or humidifier dripping onto the motor or harness.
- A control board fault on the furnace itself.
Safe Checks You Can Do First
- Restart the furnace once. Turn off the switch next to the furnace (it looks like a light switch) for 30 seconds, then turn it back on. A brief electrical glitch can clear.
- Check for water on or around the furnace, especially below the AC coil or humidifier.
- Make sure the blower door is fully seated. An open door can stop the furnace too.
If code 201 comes back, stop there. Testing motor voltage and communication signals requires meters and live-circuit work, and replacing an ECM motor or module requires the correct Lennox part programmed for your furnace.
What a Technician Will Check
We test power to the motor, inspect and test the communication harness end to end, check the motor module and motor, and confirm the control board is sending the correct signals. That tells us whether you need a harness repair, a motor module, a motor or a control board, so you pay for the actual fix and not a guess. Our trucks carry common Lennox parts, and as a Lennox Premier Dealer we can get Lennox-specific motors and modules quickly. If your furnace is still under its 10-year Lennox parts warranty, we handle the warranty claim.
Seeing a Lennox code in the Northwest Suburbs?
Pure Comfort Heating and Cooling is a Lennox Premier Dealer in Streamwood, IL. Diagnostics are $75, or $99 on evenings, weekends and holidays, and you approve a flat-rate price before any repair. Phones are answered 24/7.
Frequently Asked Questions
Can I keep running my furnace with code 201?
No. With code 201 the furnace will not run a heat cycle because it cannot confirm the blower is working. Restart it once, and if the code returns, call for service.
Is code 201 covered by the Lennox warranty?
Blower motors, motor modules and control boards are covered parts under the Lennox 10-year limited parts warranty when the furnace was registered. Labor is covered if you have extended labor coverage such as Lennox ComfortShield.
Does code 201 mean I need a new furnace?
Usually not. Code 201 is most often a wiring, motor module or motor problem that can be repaired. We give you the repair price in writing before any work begins.
How fast can you fix code 201?
Emergency calls usually get a technician within one to three hours. Many code 201 repairs are finished on the first visit when the part is in stock.
We service Lennox furnaces from our shop in Streamwood across Streamwood, Bartlett, Hoffman Estates, Schaumburg, Elgin, Hanover Park, Roselle and the rest of the Northwest Suburbs.
Looking up a different code? See our full Lennox furnace error code guide.