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    High Priority Issue

    Furnace Won't Turn On?

    When your furnace refuses to start, here's what could be wrong and when you need professional help.

    Get Same-Day Diagnosis

    Quick DIY Checklist (Try These First)

    Thermostat set to HEAT
    Temperature above room temp
    Thermostat batteries fresh
    Circuit breaker ON
    Furnace power switch ON
    Gas valve open

    Common Causes & Solutions

    Thermostat Issues

    Low PriorityDIY Fix

    Thermostat not set correctly, dead batteries, or malfunctioning.

    Solution: Check thermostat is set to HEAT, temperature is above room temp, and replace batteries if needed.

    Tripped Circuit Breaker

    Low PriorityDIY Fix

    The furnace's electrical circuit has tripped.

    Solution: Locate your electrical panel and reset the furnace breaker. If it trips again, call a professional.

    Furnace Switch Turned Off

    Low PriorityDIY Fix

    The power switch on or near the furnace is in the OFF position.

    Solution: Locate the switch (looks like a light switch) near your furnace and flip it to ON.

    Clogged Air Filter

    Low PriorityDIY Fix

    Severely clogged filter triggered safety shutdown.

    Solution: Replace the air filter and try restarting the furnace.

    Gas Valve Closed

    Medium PriorityDIY Fix

    The gas supply to the furnace has been shut off.

    Solution: Check that the gas valve handle is parallel to the gas line (open position).

    Ignition System Failure

    High PriorityCall Pro

    Electronic igniter or pilot light has failed.

    Solution: Professional diagnosis and repair of ignition components required.

    Flame Sensor Malfunction

    Medium PriorityCall Pro

    Dirty or failing flame sensor prevents ignition sequence.

    Solution: Professional cleaning or replacement of flame sensor.

    Control Board Failure

    High PriorityCall Pro

    The furnace's main control board has malfunctioned.

    Solution: Professional diagnosis and potential board replacement.

    When to Call a Professional

    • All DIY checks completed but furnace still won't start
    • Circuit breaker keeps tripping
    • You smell gas near the furnace
    • Error codes displayed on furnace
    • Furnace attempts to start but shuts down immediately

    Diagnostic Visit — $199

    An EPA-certified technician inspects your system, identifies the issue, and applies the $199 fee toward any approved repair.

    EPA-Certified TechniciansSame-Day AvailableCredit Toward Repairs

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