Trane Furnace Error Code 120: Limit Switch Open
Your Trane furnace has stored error Code 120 because the primary limit switch opened indicating the furnace is overheating. This is a safety-related diagnostic code that helps protect your system from further damage. BC Wide Home Services Ltd, doing business as BC Wide Heating & Air Conditioning provides expert diagnostic service for all Trane error codes throughout Greater Vancouver, with technicians who understand the specific conditions that trigger each code.
Diagnosing Trane Error Code 120
Professional diagnosis of error Code 120 involves several steps. Our technicians begin by retrieving the stored fault code from the control board's memory, then systematically test each potential cause. This includes measuring electrical values with multimeters, checking sensor resistance readings, verifying gas pressure, inspecting wiring harnesses for damage, and testing components individually. BC Wide Home Services Ltd, doing business as BC Wide Heating & Air Conditioning uses manufacturer-recommended diagnostic procedures for all Trane error codes.
Safety Considerations for Trane Error Code 120
Error Code 120 is a safety-related diagnostic code designed to protect your home and equipment. If you notice any unusual smells, sounds, or visible issues alongside this error code, prioritize safety. If you smell gas or suspect carbon monoxide, evacuate immediately and call emergency services from outside. Do not attempt electrical repairs or gas valve adjustments yourself. BC Wide Home Services Ltd, doing business as BC Wide Heating & Air Conditioning technicians are licensed, insured, and trained to handle all Trane error codes safely.
How BC Wide Resolves Trane Error Code 120
When you call BC Wide Home Services Ltd, doing business as BC Wide Heating & Air Conditioning for error Code 120 on your Trane system, our dispatch team will note the error code and schedule the appropriate technician. Our service vehicles carry commonly needed parts for Trane equipment, including dirty air filter and undersized ductwork replacement components. We provide upfront pricing, clear explanations of the diagnosis, and professional workmanship on every repair. Most error Code 120 diagnoses are completed within the first hour of the service call.
Cost to Fix Trane Error Code 120
The cost to resolve error Code 120 on your Trane furnace depends on the root cause. Simple fixes like cleaning a flame sensor or replacing a capacitor are relatively affordable. More involved repairs such as gas valve replacement, control board replacement, or heat exchanger service will be more significant. BC Wide Home Services Ltd, doing business as BC Wide Heating & Air Conditioning provides a detailed diagnosis and written estimate before any work begins, so you can make an informed decision about the repair.
Preventing Trane Error Code 120 in the Future
Regular maintenance is the best way to prevent error Code 120 and other fault codes on your Trane system. Annual professional maintenance includes cleaning the flame sensor, inspecting wiring connections, checking gas pressure, verifying proper airflow, and testing all safety controls. BC Wide Home Services Ltd, doing business as BC Wide Heating & Air Conditioning offers comprehensive maintenance programs for Trane equipment. Well-maintained systems have fewer error codes and emergency service calls.
Safety Reminder
If you smell gas, suspect carbon monoxide or believe there is an immediate danger, leave the property and contact emergency services or the appropriate gas emergency authority. Do not remain inside — exit the building immediately and call for help from outside.