HVAC technician repairing a Lennox furnace in a GTA home
Authorized Lennox Dealer

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 overtime fees.

Authorized Lennox Dealer
All Lennox Models Serviced
Same-Day Availability
$0 Overtime Fees
TSSA-Certified Technicians

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 CodeMeaningTypical Fix
E200Ignition failure: gas valve or igniter issueCheck gas supply is on; clean or replace hot surface igniter
E227Pressure switch fault: inducer or flue blockageInspect exhaust vent for obstruction; test inducer motor pressure
E012 / E311High-limit switch tripped (overheating protection)Replace clogged air filter immediately; check for blocked supply vents
E223Rollout switch tripped (flame outside combustion area)Requires immediate professional inspection. Do not reset without diagnosis.
E230Flame sensor fault: burner not confirmed after ignitionClean flame rod with fine steel wool; verify gas manifold pressure
E250Draft pressure fault: inducer speed issueCheck flue vent for blockage; inspect inducer motor and pressure tubing

Not sure what your code means? Call us. We diagnose over the phone for free.

Common Lennox Furnace Repairs

Lennox furnace won't ignite
Failed HSI igniter, pressure switch fault, or no gas supply
Furnace blows cold air
High-limit switch tripped: almost always a dirty filter or blocked duct
Error code on display panel
Lennox uses digital display codes, easier to diagnose than flash codes
Burners won't stay lit
Dirty or failed flame sensor rod, common on 8–12 year old units
Variable-speed blower running continuously
Control board issue or communicating thermostat misconfiguration
Lennox iComfort thermostat connectivity lost
Wi-Fi module fault or firmware issue requiring SIM card reset

Lennox Models We Service

SLP99V
98.7% AFUE modulating variable-speed. Lennox's top tier, whisper-quiet.
EL296V
96% AFUE two-stage variable-speed. Best balance of efficiency and value.
SL280V
80% AFUE single-stage variable-speed. Budget replacement option.
EL280
80% AFUE single-stage, entry-level replacement for older systems

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.

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Why 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 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 20–25 years. 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. E227 means pressure switch fault, E200 means ignition failure, E012/E311 means the high-limit switch tripped (usually a clogged filter). 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 that still qualifies for Ontario rebates. 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 overtime fees.