Lennox HVAC Systems (AC, Furnaces & Heat Pumps)

20 known error codes

201 Moderate

Pressure Switch Stuck Open

202 Moderate

Pressure Switch Stuck Closed

211 Moderate

Ignition Failure

214 Easy Fix

Flame Sense Lost During Operation

221 Moderate

Gas Valve Relay Failure

224 Easy Fix

Secondary Voltage Fuse Open

227 Easy Fix

3-Amp Fuse Open

231 Moderate

Line Voltage Reversed

241 Moderate

Low Temperature Rise

242 Moderate

High Temperature Rise

250 Easy Fix

Dirty Filter Detection

261 Moderate

Blower Motor Fault

270 Easy Fix

Low Flame Current

271 Moderate

Flame Current Leaves Acceptable Range

281 Moderate

Twinning Error

290 Moderate

Indoor Coil Thermistor Fault

292 Moderate

Outdoor Thermistor Fault

411 Moderate

Communication Fault Between Indoor and Outdoor Units

421 Moderate

Electronic Air Cleaner (EAC) Fault

E1 Moderate

High/Low Pressure Lockout