Lennox Furnace Repair and Installation in Mississauga and the GTA
Expert Lennox furnace repair, maintenance, and replacement across Mississauga, Toronto, Brampton, and the GTA. TSSA-certified technicians, same-day service, $0 residential overtime fees.
Lennox Furnace Error Codes: Diagnostic Guide
Lennox SLP and EL series furnaces use a digital display for fault codes. Here's what the most common codes mean and the typical fix.
| Error Code | Meaning | Typical Fix |
|---|---|---|
| E200 | Hard lockout: rollout circuit open (flame outside combustion area) | Requires immediate professional inspection. Do not reset. |
| E223 | Low pressure switch failed open: vent or inducer problem | Check outdoor vent pipes for snow or ice; otherwise call a technician |
| E241 | Flame sensed out of sequence: possible gas valve leak | Gas safety issue. Turn the furnace off and call a technician immediately |
| E250 | Limit switch circuit open (overheating protection) | Replace clogged air filter; check for blocked supply vents |
| E270 | Soft lockout: too many ignition retries, no flame sensed | Confirm the gas valve is open; call a technician if it returns |
| E290 | Ignitor circuit fault | Requires technician diagnosis and ignitor testing |
Not sure what your code means? Call us. We diagnose over the phone for free.
Common Lennox Furnace Repairs
Lennox Models We Service
Same-Day Lennox Repair
Most Lennox repairs are completed same-day. Our service trucks carry common Lennox parts including HSI igniters, flame sensors, pressure switches, and control boards.
Call NowWhy Choose EcoFrost for Lennox Furnace Service?
Authorized Lennox Dealer
EcoFrost is a licensed Lennox dealer. Installations are registered to activate your full manufacturer warranty.
Honest Diagnosis
We tell you honestly whether to repair or replace. No unnecessary upsells.
Same-Day Service
Most Lennox repairs completed same day with parts from our stocked service trucks.
$0 Residential Overtime Fees
Night, weekend, or holiday: same rate always. No surprise charges.
Lennox Furnace FAQs
How long do Lennox furnaces typically last?
A well-maintained Lennox furnace typically lasts 15 to 20 years, and up to 25 with good maintenance. Lennox builds premium equipment with high-quality heat exchangers. Annual maintenance and prompt minor repairs are the biggest factors in maximizing lifespan.
Is Lennox a good furnace brand?
Lennox is widely considered a top-three North American furnace brand. Their SLP99V achieves up to 98.7% AFUE, among the highest available, and their variable-speed technology delivers superior comfort and efficiency. EcoFrost is an authorized Lennox dealer.
My Lennox furnace is showing an error code. What does it mean?
Lennox SLP and EL series furnaces show digital error codes. On SL280-style controls, E250 means the limit switch opened (usually a clogged filter), E270 means an ignition lockout, and E200 means the rollout circuit opened (do not reset). Codes vary by model, so check the chart on your furnace door. Call us for a free phone diagnosis before booking a service call.
Does EcoFrost service Lennox furnaces in Mississauga and Toronto?
Yes. EcoFrost is an authorized Lennox dealer and services all Lennox furnace and AC models across Mississauga, Toronto, Brampton, Vaughan, and the full GTA. Same-day service available.
What is the difference between the Lennox SLP99V and EL296V?
The SLP99V is Lennox's top-of-line modulating furnace (98.7% AFUE), adjusting output in tiny increments for the quietest, most efficient operation. The EL296V is a two-stage 96% AFUE model, a great value choice. Note that gas furnaces, including both of these, have no Ontario rebate in 2026. The SLP99V costs roughly $1,500-$2,000 more installed but delivers lower gas bills over time.
Lennox Furnace Problem? We Fix It Today.
Same-day service across Mississauga, Toronto, Brampton, and the GTA. Authorized Lennox dealer. $0 residential overtime fees.