Lennox Furnace Repair: Common Issues

Lennox furnaces often display a diagnostic code when a heating cycle fails, and that code can help us decide where to start with furnace inspection and repair. If your Lennox furnace is showing an error, we can use it to help diagnose the issue and make repairs. 

We provide furnace repair in Edmonton for Lennox and other top heating brands. If you see a code, write it down or take a photo before it disappears. We’ll check it against your furnace model and inspect the system to confirm the cause. 

Check What the Code Means for Your Model 

Lennox uses different controls across its furnace models. The examples below come from a Lennox SL280 manual, so they are a guide to what you might see, rather than a code list for every Lennox furnace.  

E207: The furnace has detected a problem with the hot surface ignitor, which helps light the burners. 

E223: The low pressure switch did not close as expected. We would check the venting and the fan that moves combustion air before concluding the switch has failed. 

E227: The low pressure switch opened while the furnace was trying to light or while it was running. 

E229: The furnace lit on its higher heat setting because the low heat pressure switch did not close in time. Lennox lists this as an informational code that needs no action on its own. 

E240: The furnace detects a weak flame signal while running. The flame sensor and related electrical conditions need to be checked. 

E250: A temperature limit circuit is open. We would investigate airflow and what may be causing the furnace to get too hot. 

E270: The furnace has stopped retrying after it could not confirm a flame. Ignition, gas flow and flame detection are among the things we would check. 

These codes describe what the furnace detected. For example, E223 does not necessarily mean you need a new pressure switch. The problem could be elsewhere in the process that lets the furnace vent and start safely. 

Notice What Happens Alongside the Alert 

Tell us whether the furnace stops before producing any heat, runs briefly and shuts off or continues heating despite the code. Does the same alert return every time? Did the problem begin during particularly cold weather? 

Those details help us connect the code to what the furnace is doing. They are especially useful if the fault comes and goes and the system is running by the time we arrive. 

Call Hydro-Flo for Furnace Repair in Edmonton 

When you call, give us the code and the Lennox model number if you have it. Do not worry if you cannot find the model information. We can identify the furnace during the visit. 

We’ll use the correct model information, test the components involved and explain what needs repair. If your Lennox furnace has stopped heating or keeps showing an alert, give Hydro-Flo a call so we can get to the cause. 

780-203-2230 

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