Lennox Furnace Error Code E274: How to Fix It

Q: What causes Lennox error code E274?

Error E274 is caused by a faulty outdoor coil temperature sensor that's either open (broken connection) or shorted (electrical fault). Common causes include sensor failure due to age, damaged wiring from weather or rodents, or loose electrical connections.

Q: Can I run my Lennox furnace with error code E274?

No, you should not run your furnace with error E274. The system will likely shut down to protect itself from potential damage. The outdoor coil sensor is critical for safe operation and preventing compressor damage from extreme temperatures.

Q: How much does it cost to fix Lennox error E274?

DIY repair typically costs $20-50 for a replacement sensor. Professional repair usually ranges from $150-300 depending on labor rates and whether additional wiring work is needed. The sensor itself is relatively inexpensive, but labor for diagnosis and replacement adds to the cost.

Q: How long do Lennox coil temperature sensors last?

Lennox outdoor coil temperature sensors typically last 5-10 years depending on environmental conditions. Sensors exposed to extreme weather, high humidity, or frequent temperature cycling may fail sooner. Regular maintenance can help extend sensor life.

Q: Will error code E274 reset itself?

Error code E274 will not reset itself until the underlying sensor problem is fixed. Simply turning the system off and on will not clear this error. The faulty sensor must be repaired or replaced for normal operation to resume.

Abstract

Lennox furnace error code E274 indicates that the outdoor coil temperature sensor is either open (broken connection) or shorted (electrical fault). This sensor monitors the temperature of your heat pump's outdoor coil to ensure proper operation and prevent damage from extreme conditions.