Goodman Furnace Won’t Ignite: Troubleshooting and Fixes

The inability of a Goodman furnace to ignite is a common problem that interrupts home heating and can stem from simple fixes to safety-related failures. This article guides readers through how ignition systems work, common causes of ignition failure, step-by-step troubleshooting, safety precautions, likely repair costs, and when to call a licensed technician. Keywords: Goodman Furnace Won’t Ignite, Goodman furnace troubleshooting, ignition problems.

Symptom	Common Cause	Quick Fix
Igniter Not Glowing	Failed hot surface igniter or no power	Check breaker/transformer, replace igniter
Clicking But No Flame	Gas valve issue or weak gas pressure	Verify gas supply and valve operation
Blower Runs Without Ignition	Limit switch or control board fault	Inspect sensors, reset or replace control board

How A Goodman Furnace Ignition System Works

Understanding ignition basics helps diagnose why a Goodman furnace won’t ignite. Most modern Goodman furnaces use either a hot surface igniter (HSI) or an intermittent pilot/electronic ignition system to light burners.

When the thermostat calls for heat, the control board initiates a sequence: inducer/blower runs, pressure switch verifies airflow, igniter receives voltage to heat or a spark is generated, and the gas valve opens to allow fuel to the burners.

If any component in that sequence fails — safety switch, igniter, control board, gas valve, or sensors — the furnace may not light. Identifying at which step the sequence stops narrows the likely causes.

Common Causes Why A Goodman Furnace Won’t Ignite

1. Thermostat Or Power Issues

A misconfigured thermostat, dead batteries, tripped breaker, or switched-off furnace power can prevent ignition. Always verify power and thermostat settings first before deeper troubleshooting.

2. Failed Hot Surface Igniter Or Ignition Module

HSIs crack or burn out after repeated cycles. A visible crack or absence of glow indicates failure. Electronic ignition modules can also fail and will prevent spark or heating sequence.

3. Faulty Flame Sensor

The flame sensor detects burner flame and will shut off the gas valve if it doesn’t sense flame, causing repeated shutdowns or no ignition if the sensor is dirty, misaligned, or failing.

4. Gas Supply Or Gas Valve Problems

No gas to the furnace, a closed gas shutoff, or a failing gas valve will prevent burners from lighting. Low fuel pressure from the utility or a blocked line also causes failure to ignite.

5. Pressure Switch, Inducer Motor, Or Venting Issues

Blocked venting or a failing inducer motor can keep the pressure switch from closing, stopping the ignition sequence. The pressure switch ensures safe combustion venting.

6. Control Board Or Limit Switch Failures

The control board orchestrates the ignition steps. A faulty board, burned connectors, or a tripped high-limit safety switch can interrupt ignition even when other parts are functional.

Step-By-Step Troubleshooting For A Goodman Furnace That Won’t Ignite

Safety First

Before starting, turn off power to the furnace at the switch and breaker and shut off the gas valve if working near fuel components. If the smell of gas is present, evacuate and call the gas company or emergency services.

Basic Checks

• Confirm thermostat calls for heat and has fresh batteries if applicable.
• Check the furnace power switch and circuit breaker; reset if tripped.
• Ensure the furnace door/panel is fully seated; many units have safety interlocks.

Observe The Ignition Sequence

Restore power, set the thermostat to heat, and watch the furnace. Note whether the inducer starts, whether a clicking or glowing igniter appears, whether the gas valve opens, and whether the burners light.

Diagnostic Steps Based On Symptoms

• No Inducer/No Activity: Check 120V power to the inducer and wiring; the control board may be dead.
• Inducer Runs But No Igniter Glow/Spark: Test for 120/115V or 24V to the igniter or ignition module; replace igniter/module if no voltage or if igniter doesn’t glow when powered.
• Igniter Glows But No Gas: Verify gas valve receives 24V when the igniter is hot. If not, control board or wiring may be at fault. If 24V present but no gas, the gas valve may be defective.
• Burners Light Then Go Out: Inspect and clean the flame sensor; replace if pitted or failing.
• Clicking With No Flame: Could indicate transformer/ignition module issues or blocked gas supply.

Testing Components

Use a multimeter and follow manufacturer specs: measure continuity of HSI (resistance usually in tens of ohms when cold), check for 24VAC across gas valve terminals when call for heat, and test flame sensor millivolt output during operation.

Safety Precautions And Gas Leak Response

Working with gas appliances carries combustion and asphyxiation risks. If a strong gas odor exists, avoid using electrical switches and ventilate the area while evacuating until professionals arrive.

Only qualified HVAC technicians should perform gas valve replacement, pressure testing, or work requiring gas piping adjustments. Homeowners can safely perform visual checks, replace easily accessible igniters per instructions, and clean the flame sensor with fine emery cloth.

When To Call A Professional Technician

Call a licensed HVAC technician if the problem involves gas valves, control board replacement, inducer motor removal, complex wiring, recurring ignition failure, or if safety switches repeatedly trip. Certified techs handle combustion analysis, leak testing, and warranty-covered repairs.

Immediate professional help is recommended when there is persistent gas odor, repeated flame rollout or limit-switch trips, or if the furnace is under warranty and replacement parts are needed.

Common Parts That Fail And Replacement Costs

Typical parts that cause ignition failure include hot surface igniters, flame sensors, gas valves, ignition control modules, pressure switches, and control boards.

Part	Typical DIY Cost	Estimated Professional Repair
Hot Surface Igniter	$30–$120	$150–$350 (parts + labor)
Flame Sensor	$10–$50	$80–$200
Gas Valve	$100–$350	$300–$700
Control Board	$80–$400	$250–$800

Prices vary by model and region. Professional service calls, diagnostics, and safety checks add to labor costs. Always compare multiple quotes and confirm licenses and insurance.

Preventive Maintenance To Reduce Ignition Failures

Scheduled maintenance extends furnace life and reduces no-heat calls. Annual tune-ups before heating season should include inspection of the ignition system, cleaning the flame sensor, checking venting and pressure switches, and testing safety controls.

• Replace air filters every 1–3 months to ensure proper airflow and prevent limit trips.
• Keep the area around the furnace clean and free of dust and debris.
• Inspect condensate drains and venting annually for blockages.
• Enroll in a maintenance plan with a licensed HVAC company for priority service.

Troubleshooting Tips Specific To Goodman Furnaces

Goodman units often use robust, modular control boards and common OEM igniters. Check the model-specific wiring diagram inside the access panel to trace signals during the ignition sequence.

Goodman furnaces include diagnostic LED codes on the control board that flash to indicate faults. Consult the furnace’s data plate or manual to decode flash patterns; this often points directly to pressure switch, limit, or flame sensor faults.

Frequently Asked Questions

Why Is The Igniter Not Glowing On A Goodman Furnace?

Most often due to a failed HSI, lack of 120/24V power to the igniter circuit, or a control board that doesn’t send voltage. Confirm power and test or replace the igniter as needed.

Can A Dirty Flame Sensor Prevent Ignition?

A dirty flame sensor usually causes burners to shut off after ignition but rarely prevents the initial spark or glow. Cleaning the sensor often resolves flame detection problems.

Is It Safe To Try Replacing The Igniter Myself?

Replacing a hot surface igniter is a common DIY task if the homeowner is comfortable with basic electrical isolation and handling fragile ceramic parts. Always disconnect power and follow the manufacturer’s instructions.

How Long Do Hot Surface Igniters Last?

Typical HSIs last 3–10 years depending on cycles and operating conditions. Signs of imminent failure include slow glow, visible cracking, or intermittent operation.

Resources And Next Steps

For accurate part numbers and wiring diagrams, reference the furnace model number on the data plate and consult Goodman documentation or the installer manual. Keep records of maintenance, error codes, and service visits for warranty and troubleshooting history.

If the furnace won’t ignite after these checks, contact a licensed HVAC technician. Provide the technician with observed behaviors, LED error codes, and steps already taken to speed diagnosis and repair.