Arcoaire Furnace Pilot Light Troubleshooting, Relighting, and Safety Guide

The Arcoaire furnace pilot light plays a critical role in starting and maintaining home heating systems. This guide explains how the pilot light works, step-by-step relighting procedures, common causes of pilot outages, safety precautions, maintenance tips, and when to call a professional. It aims to give clear, actionable information for U.S. homeowners dealing with Arcoaire furnace pilot light issues.

Topic	Quick Summary
Function	The pilot light ignites the main burner when the thermostat calls for heat.
Relighting	Follow manufacturer instructions: turn gas off, wait, set to pilot, ignite, hold valve 30–60 seconds.
Common Causes	Clogged pilot tube, faulty thermocouple, gas supply issues, drafts, ignition switch failure.
Safety	Ventilate for gas smell, shut off gas, avoid open flames, call licensed technician for leaks or repeated outages.

How The Arcoaire Furnace Pilot Light Works

The pilot light is a small continuous flame that ignites the main burner when the thermostat signals for heat. In many Arcoaire furnaces, the pilot assembly includes a pilot tube, thermocouple or thermopile, and a gas valve. The thermocouple senses heat from the pilot flame and keeps the gas valve open. When the pilot goes out, the thermocouple cools and closes the valve to prevent unburned gas from flowing.

Common Symptoms Of Pilot Light Problems

Recognizing symptoms early can prevent system damage and safety risks. Common signs include a furnace that won’t start, a gas odor near the furnace, frequent pilot outages, noisy ignition attempts, and a weak or yellow pilot flame instead of a steady blue flame. A weak or yellow flame often indicates combustion or airflow problems.

Step-By-Step: Relighting An Arcoaire Furnace Pilot Light

Relighting the pilot light is often a safe homeowner task if the furnace uses a manual pilot. Always consult the Arcoaire owner manual for model-specific procedures. If the furnace has electronic ignition, do not attempt manual relighting—contact a technician.

Preparation And Safety First

Turn off power to the furnace at the breaker and set the thermostat to OFF. Locate the gas valve on the furnace, usually labeled OFF, ON, and PILOT. Ensure proper ventilation and avoid open flames if a gas odor is present. If a strong gas smell exists, leave the home and call the gas company immediately.

Relighting Procedure

1. Set The Gas Valve To OFF And Wait: Turn the gas control knob to OFF and wait five minutes to allow any accumulated gas to dissipate.
2. Set To PILOT: Turn the knob to PILOT and depress it to start gas flow to the pilot assembly.
3. Ignite The Pilot: Use a long-reach butane lighter or match to ignite the pilot while holding the gas control knob depressed. On many Arcoaire units a piezo igniter may be present—press it while holding the valve in PILOT.
4. Hold The Valve: Continue holding the gas control knob for 30–60 seconds after ignition to allow the thermocouple to heat sufficiently and register the flame.
5. Release And Set To ON: Slowly release the knob. If the pilot stays lit, turn the valve to ON and restore power to the furnace.
6. Test The Furnace: Set the thermostat to call for heat and observe several ignition cycles to ensure the pilot reliably lights the main burner.

Why The Pilot Light Keeps Going Out

Frequent pilot outages can stem from several issues. Clogged pilot orifice prevents sufficient gas flow. A faulty thermocouple or thermopile can fail to sense heat and shut the gas valve. Drafts in the furnace room can blow out the pilot. Loose or damaged wiring to safety controls or a failing gas control valve also causes outages. Regular inspection helps pinpoint the cause.

Pilot Orifice And Tube Blockages

Dust, spider webs, and combustion residues can block the tiny pilot orifice. Cleaning requires careful use of compressed air or a thin wire; however, improper cleaning may damage components. If the pilot assembly is heavily corroded, replacement is safer and more effective.

Thermocouple And Thermopile Issues

The thermocouple converts the pilot flame’s heat into a millivolt signal that keeps the gas valve open. A damaged or misaligned thermocouple won’t reach the flame and will shut the gas supply. Thermopiles in newer systems generate more voltage and can fail similarly. Testing with a multimeter can confirm failure; replacement is a common repair.

Safety Precautions And Gas Leak Response

Handling gas appliances demands caution. If a homeowner detects a rotten-egg smell, which indicates natural gas, they should evacuate the home immediately, avoid switching electrical devices on or off, and call the gas company or 911 from a safe location. Do not attempt repairs if a leak is suspected.

Carbon Monoxide And Venting

Improper combustion or blocked venting can produce carbon monoxide (CO). CO is colorless and odorless. Install CO detectors on every level and near sleeping areas. If CO detectors alarm, exit the home and seek emergency help. Regular furnace inspections reduce the risk of dangerous combustion byproducts.

Maintenance Tips To Prevent Pilot Light Problems

Routine maintenance increases reliability and efficiency. Annual professional tune-ups are recommended, including burner and heat exchanger inspection, pilot assembly cleaning, and safety control testing. Homeowners can keep the furnace area clean and free of drafts, replace air filters regularly, and ensure the venting path is clear of debris or bird nests.

• Keep The Area Clean: Remove dust and stored items around the furnace to reduce drafts and debris buildup.
• Replace Air Filters: Change filters every 1–3 months depending on use and filter quality.
• Check Pilot Flame Color: A steady blue flame indicates healthy combustion; yellow tips suggest soot or combustion issues.
• Schedule Annual Service: Hire an HVAC professional to perform a comprehensive inspection before the heating season.

When To Call A Professional HVAC Technician

Some pilot light issues require trained technicians. Call a licensed HVAC professional when there is a persistent pilot outage, a suspected gas leak, faulty thermocouple or gas valve, malfunctioning pressure switches, or failed electronic ignition systems. Technicians can perform safe diagnostics, replace parts, and verify safe operation and ventilation.

Costs And Typical Repairs

Costs vary by region, unit age, and repair complexity. Typical thermostat or pilot relight service calls range widely; expect a diagnostic fee plus parts. Common repairs include thermocouple replacement ($100–$250 installed), pilot assembly cleaning or replacement ($100–$300), and gas valve replacement ($300–$700). Electronic ignition system repairs can be more expensive.

Model-Specific Notes For Arcoaire Furnaces

Arcoaire furnaces may use standing pilot systems on older models or electronic ignition on newer units. Model-specific owner manuals include the exact pilot relighting sequence and safety warnings. For Arcoaire units with a sealed combustion chamber, homeowners should not attempt internal repairs and should contact a qualified technician for any internal access.

DIY Troubleshooting Checklist

Before calling for service, a homeowner can run through a safe checklist to identify simple causes and provide technicians useful information.

1. Check Thermostat Settings: Ensure the thermostat is set to HEAT and temperature is above the current room temp.
2. Verify Power And Gas Supply: Confirm the furnace has power and the gas shutoff valve at the appliance is open.
3. Inspect Pilot Flame: Look for a steady blue flame and proper positioning on the thermocouple.
4. Listen For Clicking Or Snapping: Ignition noises may indicate intermittent ignition problems.
5. Document Patterns: Note how often the pilot goes out and any recent storms, power outages, or maintenance changes.

Frequently Asked Questions About Arcoaire Furnace Pilot Light

Can A Pilot Light Cause A Gas Leak?

A pilot light itself does not cause a gas leak. However, if the pilot is out and the gas control fails to shut off, unburned gas can accumulate. Modern safety controls typically prevent this, but any suspected gas leak requires immediate evacuation and professional response.

Is It Safe To Relight The Pilot After A Power Outage?

Yes, if the unit uses a manual pilot and there is no gas odor. Follow the relighting procedure and wait five minutes after switching gas back on to clear any accumulated gas. If the furnace has an electronic ignition, the system will handle relighting automatically; consult the manual if it does not.

How Long Should The Pilot Stay Lit After Releasing The Valve?

After holding the gas control knob for 30–60 seconds and releasing it, the pilot should stay lit immediately. If it goes out, the thermocouple may not be heating properly, or the pilot flame may be misaligned or weak.

Resources And Next Steps

For model-specific procedures, consult the Arcoaire owner manual or the manufacturer’s website. Homeowners should keep a record of maintenance and service calls. If repeated pilot problems occur, schedule a professional inspection to evaluate the burner assembly, gas valve, venting, and safety controls.

For immediate safety concerns call the local utility gas emergency line or 911, and for repairs contact a licensed HVAC contractor.