Lennox Furnace Error Code E311: How to Fix It

Q: What causes Lennox error code E311?

Error code E311 is caused by a low pressure switch trip, typically due to low refrigerant levels, refrigerant leaks, blocked air filters, dirty coils, or a faulty pressure switch.

Q: Can I reset Lennox error code E311 myself?

You can try resetting the system by turning off power for 5 minutes, but if the underlying cause isn't fixed, the error will return. Address the root cause rather than just resetting.

Q: How much does it cost to fix E311 error on Lennox furnace?

Repair costs vary from $150-$300 for simple fixes like filter replacement or pressure switch replacement, up to $500-$1500 for refrigerant leaks or major component replacement.

Q: Is it safe to run my Lennox furnace with E311 error?

No, do not run the furnace with an active E311 error. This can damage the compressor and other components, leading to much more expensive repairs.

Q: How often should I change my furnace filter to prevent E311?

Change your furnace filter every 1-3 months depending on usage and filter type. A clogged filter reduces airflow and can contribute to pressure switch issues.

Abstract

Error code E311 on your Lennox furnace indicates a low pressure switch trip, typically caused by low refrigerant levels or a restriction in the refrigerant system. This is a serious issue that requires immediate attention as it can damage your compressor if left unresolved.