Quick answer: Lennox code 229 (E229) is an information code, not a lockout. It means the furnace lit on high fire because the low-fire pressure switch did not close at low inducer speed. Your furnace keeps heating, but if code 229 appears often, it points to a draft, drainage or inducer problem that should be checked before it becomes a no-heat code.
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 229 Mean?
Lennox two-stage and variable-capacity furnaces normally start on low fire. Lennox documents code 229 as Ignition on High Fire, information only, displayed when the low pressure switch fails to close. Instead of stopping, the furnace switches the inducer to high speed and lights on high fire so you still get heat.
Common Causes of Code 229
- Partial vent restriction from snow, ice or debris at the outside pipes.
- A partly clogged condensate trap or drain on high-efficiency furnaces.
- Water or a kink in the low pressure switch tubing.
- A weak inducer motor that can still prove draft at high speed but not at low speed.
- A low-fire pressure switch that is drifting out of range.
Should You Worry About Code 229?
One occasional code 229 is not an emergency. Frequent 229 codes mean the furnace is working around a problem. Left alone, the same causes often lead to code 223 or 227, which stop the furnace completely, usually on the coldest night.
Safe checks: clear snow and debris from around the outside PVC pipes and look for water around the furnace or a clogged drain line. Never bypass a pressure switch.
What a Technician Will Check
We measure draft at low and high inducer speed with a manometer, clean and test the condensate trap and tubing, inspect the venting, and evaluate the inducer and both pressure switches. Fixing it now is usually simpler than waiting for a no-heat call. A yearly furnace tune-up catches these problems early.
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
Is my furnace still safe to run with code 229?
Yes. Code 229 is information only and the furnace still heats. Have it checked if the code appears regularly, because it usually points to a developing draft or drainage problem.
Why does my Lennox furnace go straight to high fire?
If the low pressure switch does not close at low inducer speed, the control lights on high fire and logs code 229. A restricted vent, clogged trap or weak inducer is usually the cause.
Can code 229 turn into a bigger problem?
Yes. The same causes can progress to codes 223 or 227, which shut the furnace down. Addressing it early avoids a no-heat call.
Is this covered during a tune-up?
Our 49-point furnace tune-up includes checking the venting, condensate trap and pressure switch operation, which is how many code 229 problems are found and fixed.
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.