The Intertherm Furnace Reset Button is a small but important safety feature on many gas furnaces. This article explains where to find the reset button, when to press it, how to follow safe reset procedures, common causes that trip it, troubleshooting steps, and when to call a professional.
| Topic | Quick Facts |
|---|---|
| Purpose | Manual Safety Reset For Overheat/Limit Trips |
| Typical Location | Near Blower Or On Furnace Control Panel |
| When To Press | After Cooling And Diagnosing Cause |
| Do Not Do | Repeatedly Press Without Fixing Underlying Issue |
What The Intertherm Furnace Reset Button Is
The Intertherm furnace reset button is a manual switch designed to protect the unit from damage after an overheat or fault condition. It generally interrupts power to the blower or gas valve until the user confirms the issue has been addressed.
This button acts as a secondary safeguard beyond electronic limit switches and control board protections. It is not a standard on/off switch, and its repeated use without correct diagnosis can mask underlying dangers.
Where To Find The Reset Button
Intertherm furnaces vary by model, but common locations for the reset button include inside the blower compartment, on the control panel behind the service access panel, or near the gas valve assembly.
- Check The Owner’s Manual First — Model-specific diagrams show button locations.
- Remove The Furnace Access Panel — Power should be off before removing panels to inspect internal components.
- Look For A Small Red Or Black Button — It may be recessed or labeled “Reset.”
When It Is Appropriate To Press The Reset Button
Press the reset button only after the furnace has cooled and a basic inspection suggests it is safe to attempt a restart. Typical triggers include an overheated heat exchanger, blocked exhaust/venting, failed blower motor, or temporary power surge.
Do Not Press Immediately After A Trip. Allow at least 10–20 minutes for cooling, and always verify that the cause is not a persistent problem like blocked vents or a failed motor.
Step-By-Step Safe Reset Procedure
Follow these steps to reset an Intertherm furnace safely and responsibly.
- Turn Off Power To The Furnace — Use the switch on the furnace or the circuit breaker to cut power.
- Wait For Cooling — Allow at least 10–20 minutes for internal components to cool.
- Inspect For Obvious Problems — Check vents, filters, blower area, and wiring for damage or blockages.
- Locate The Reset Button — Consult the manual or look inside the blower compartment.
- Press The Button Once — Apply steady pressure and release; do not repeatedly press the button.
- Restore Power And Observe — Turn power back on and run the furnace; watch for error codes, unusual noises, or immediate trips.
Common Reasons The Reset Button Trips
Understanding frequent causes helps prevent unnecessary resets and improves safety.
Restricted Airflow
Clogged air filters, closed return vents, or blocked ductwork reduce airflow. Insufficient airflow causes the heat exchanger to overheat and triggers limit switches and the reset.
Blower Motor Problems
A failing blower motor or capacitor can cause the blower to stall, creating heat buildup. Motor bearings or electrical faults are common mechanical causes.
Blocked Exhaust Or Venting
Obstructions in the flue or venting system prevent combustion gases from exiting, causing overheating and safety trips. Animals, debris, or collapsed vent pipes are typical obstructions.
Ignition Or Fuel Supply Issues
Repeated ignition failures or irregular gas supply lead to unsafe operating cycles. Control boards may lock out and require a manual reset if ignition or flame sensing repeatedly fails.
Electrical Surges Or Control Failures
Shorts, bad relays, or control board faults can trigger the reset button. Electrical issues should be inspected by a technician to avoid recurring trips or fire hazards.
Troubleshooting Guide After A Reset Trip
Use this systematic checklist to diagnose the root cause before resetting the furnace.
- Check The Air Filter — Replace if dirty. Filters restricted beyond recommended change intervals are a leading cause.
- Inspect Vents And Ductwork — Ensure exterior vents are clear and returns are open.
- Examine The Blower — Look for debris, belt issues, or motor overheating signs like burnt smell.
- Scan Control Panel For Error Codes — Many Intertherm units indicate faults via LED blink patterns; consult the manual for code meanings.
- Verify Gas Supply And Ignition — Confirm the gas valve is open and pilot/igniter operation is normal.
- Look For Water Or Corrosion — Condensate buildup or corrosion can affect sensors and safety switches.
Understanding Furnace Error Codes And LEDs
Intertherm furnaces often use a blinking LED to communicate faults. Identifying the blink pattern can expedite repairs.
Common codes indicate limit trips, pressure switch failures, ignition lockouts, or blower faults. Record the code pattern and consult the model-specific diagnostics table in the manual or on the control board label.
When The Reset Button Keeps Tripping
Repeated trips signal a persistent issue that must be addressed. Continued resetting risks damage to the furnace, increases carbon monoxide risk, and may void warranties.
If the reset button trips more than once after a proper inspection and basic fixes, discontinue attempts and contact a licensed HVAC technician for a thorough diagnosis.
Safety Considerations And Carbon Monoxide Risks
A malfunctioning furnace that trips its reset could also have combustion issues potentially producing carbon monoxide. Always install functioning CO detectors near sleeping areas and the furnace room.
Never run a gas furnace that smells strongly of gas or shows signs of combustion failure. Evacuate the area and call the gas company and a licensed technician immediately.
Maintenance Tips To Prevent Reset Trips
Regular maintenance reduces the chance of reset trips and prolongs furnace life.
- Replace Air Filters Every 1–3 Months Depending On Use.
- Schedule Annual Professional Tune-ups For Combustion, Venting, And Electrical Checks.
- Keep Exterior Vents Clear Of Snow, Leaves, And Debris.
- Maintain Adequate Return Air — Avoid blocking cold air returns with furniture.
- Listen For Unusual Noises And Address Them Early.
When To Call A Professional
Contact a licensed HVAC technician if any of the following apply: repeated resets, visible flame irregularities, gas smells, persistent error codes, or suspected heat exchanger cracks.
Qualified technicians have the tools to test for combustion efficiency, verify heat exchanger integrity, and inspect electrical controls safely.
Parts Replacement And Costs
Common repairs related to reset issues may include replacing air filters, blower motors, pressure switches, ignitors, control boards, or limit switches.
| Repair Type | Typical Cost Range (US) |
|---|---|
| Air Filter Replacement | $5–$50 |
| Blower Motor Replacement | $300–$900 |
| Ignitor Or Flame Sensor | $100–$300 |
| Control Board Replacement | $250–$800 |
| Pressure Switch Or Limit Switch | $100–$350 |
Costs vary by model, labor rates, and regional pricing. Always obtain multiple estimates for major repairs and verify technician licensing and insurance.
Model Variations And Documentation
Intertherm furnaces include different series and model numbers. Locator labels on the furnace or the owner’s manual will show detailed circuitry, reset button location, and LED blink code charts.
Keeping the manual handy or downloading a PDF from the manufacturer’s site expedites troubleshooting and ensures accurate interpretation of codes and safety instructions.
DIY vs Professional Repairs: What Is Safe To Do
Homeowners can perform basic preventive tasks: filter changes, clearing vents, visual inspections, and turning power off before accessing panels.
Electrical repairs, gas valve work, combustion testing, heat exchanger inspection, and control board replacement should be left to licensed professionals due to safety and legal considerations.
Preventive Checklist For Homeowners
- Replace Filters Regularly And Keep Registers Open.
- Schedule An Annual HVAC Tune-Up In Fall.
- Inspect Exterior Vent Terminals Quarterly.
- Install And Test Carbon Monoxide Detectors Monthly.
- Know The Location Of The Furnace Power Switch And Gas Shutoff.
Resources And Further Reading
Useful resources include the Intertherm/Comfortmaker product manuals, local utility safety pages, and HVAC trade associations for guidance on service standards and technician certification.
Manufacturer PDFs provide model-specific wiring diagrams and diagnostic code tables that are essential for accurate troubleshooting.
Key Takeaways
The Intertherm furnace reset button is a safety feature intended for use only after cooling and basic inspection. Repeated trips indicate underlying problems such as airflow restriction, blower failure, vent obstruction, or electrical faults. Homeowners should perform basic checks and maintenance but rely on licensed HVAC professionals for combustion, electrical, and major mechanical repairs to ensure safety and reliability.