Sherwood Mechanical Services is your family-oriented HVAC expert, servicing Sherwood Park and the surrounding areas since 2016. Our experienced technicians provide upfront pricing and satisfaction guarantees on all our reliable and efficient services including heating, cooling, gas fitting, and water heater installation. We take pride in our friendly, transparent approach, and our commitment to exceptional customer service. Repair & Installation of: AC's, Furnaces, Tankless Water Heaters, Hot Water Tanks, Boilers, Garage Heaters Upfront pricing & satisfaction guaranteed!
A garage heater that stops working in Sherwood Park in November is not a minor inconvenience — it is an urgent practical problem for homeowners who use the garage as a workshop, for vehicle protection in extreme cold, or for a secondary heated space that family members rely on through Alberta’s long winter.
The majority of garage heater failures in Sherwood Park have specific, diagnosable causes — they are not random equipment collapses. Understanding what the most common faults look like, what the diagnostic sequence is, and when repair is the right call versus replacement gives homeowners a clear picture of what to expect when they call for service.
Gas Garage Heater Faults: The Most Common Problems in Sherwood Park
1. Short-cycling (heater fires, runs briefly, shuts off)
Short-cycling is the most common operational complaint for gas garage heaters in Sherwood Park — the unit ignites, runs for a brief period, shuts off before the space reaches temperature, and the cycle repeats. The most frequent causes are:
- Dirty flame sensor: The flame sensor is a small rod that detects the presence of a flame after ignition. When it is coated with oxide deposits from normal combustion, it may fail to confirm flame presence even when the burner is firing, causing the control board to shut the gas valve as a safety measure. Cleaning the flame sensor with fine steel wool is one of the most common single-component garage heater repairs and frequently resolves short-cycling on its own.
- Restricted airflow: A gas garage heater requires an adequate supply of combustion air. If the heater is in a very tight space, if debris has accumulated at the intake, or if the unit is running in a sealed garage with no air source, restricted combustion air causes incomplete combustion and safety shutoffs.
- Overheating due to blocked discharge: If the heater’s warm air discharge is partially blocked — by stored items pushed too close to the unit, or by a wall mounted too close to the discharge — the heat exchanger overheats and triggers a high-limit safety shutoff. Clearing the discharge area and allowing the unit to cool before restarting often resolves this.
2. No ignition (heater attempts to start but no flame is established)
A gas garage heater that runs through its ignition sequence — you hear the spark or glow ignition — but fails to establish a flame points to one of several components:
- Failed igniter: A cracked or failed hot surface igniter (glow plug) or a faulty spark ignition module does not reach the temperature or produce the spark required to ignite the gas-air mixture.
- Gas supply issue: If the main gas valve to the garage is partially closed, or if the gas pressure from the supply line is inadequate, the burner cannot establish a flame. This is a less common cause but worth checking at the supply valve before assuming the igniter has failed.
- Blocked or dirty burner ports: Rust, debris, or spider nesting (a common problem in garage heaters that sit dormant through summer in Sherwood Park) inside the burner assembly can block gas flow through the ports, preventing ignition.
3. Heater runs but does not adequately heat the space
A garage heater that operates continuously without achieving a comfortable temperature is either undersized for the space at its current insulation level, has a heat exchanger partially blocked by scale or debris, or has a thermostat that is reading the ambient temperature incorrectly due to placement or calibration.
In Sherwood Park, where garage insulation levels vary widely, a heater sized for a well-insulated garage will underperform in the same garage if the door seals have degraded, a new opening has been added, or the insulation has been damaged. Our garage heater installation guide covers the sizing methodology for Sherwood Park garages in detail.
4. Unusual smells during operation
A burning dust smell at the start of the heating season — when a garage heater runs for the first time after several months dormant — is normal and resolves within the first few cycles. A persistent burning smell, a sulphur or gas smell, or a metallic odour that doesn’t clear is not normal and warrants immediate shutdown and a service call. A sulphur or gas smell indicates a gas leak and requires the unit to be shut off at the gas valve and the space ventilated before anyone re-enters.
Electric Garage Heater Faults
Electric garage heaters in Sherwood Park have fewer components than gas units but their own failure patterns.
Tripped circuit breaker: Electric garage heaters draw significant current — a 240V unit running at 5,000 watts draws approximately 21 amps on a 30-amp circuit. A heater that repeatedly trips its circuit breaker indicates either a failing heating element drawing excessive current, a loose connection generating heat at the terminal, or a circuit that is undersized for the heater’s actual draw.
Thermostat failure: The thermostat in an electric garage heater is subject to the same temperature extremes and dust environment as the rest of the unit. A failed thermostat may cause the heater to run continuously, never run, or cycle at incorrect temperatures.
Heating element failure: The resistance heating elements in an electric garage heater eventually burn through with enough operating cycles. A heater that powers on (the fan runs) but produces no heat, or one that heats at significantly reduced output, typically has one or more failed elements.
Annual Garage Heater Maintenance for Sherwood Park Homes
The best time for annual garage heater maintenance in Sherwood Park is late summer or early fall — before the heating season begins and before technician schedules fill. A fall service visit should include:
- Burner cleaning and inspection
- Flame sensor cleaning
- Ignition component check
- Heat exchanger inspection
- Venting system inspection and clearance check
- Gas pressure verification
- Thermostat calibration test
- Combustion air supply confirmation
This is exactly the scope our garage heater installation service team covers for both new and existing garage heater systems across Sherwood Park, Ardrossan, Ft Saskatchewan, and Strathcona County.
When to Replace Rather Than Repair a Garage Heater
A garage heater over 15 years old requiring its second or third significant repair in as many seasons is telling you something. The specific scenarios that point clearly toward replacement:
- Heat exchanger failure — the heat exchanger is the most expensive component in a gas garage heater, and replacement cost approaches or exceeds new unit cost on older equipment
- Repeated ignition component failures — may indicate a burner assembly problem that is feeding the ignition system failures
- A unit that is significantly undersized for the current garage configuration after insulation or space changes
- A very old low-efficiency unit where a new high-efficiency replacement delivers meaningfully better performance for the same or lower operating cost
For new garage heater installation or replacement in Sherwood Park, our garage heater installation page covers the full scope of what a properly sized and installed unit involves. Financing is available for garage heater replacement. Contact Sherwood Mechanical to book a garage heater service or repair call, or call (780) 449-5322.
