Call (516) 259-1191
    home+ — Home+ Air and Heat
    ES (516) 259-1191
    Common Issue

    Furnace Blowing Cold Air?

    When your furnace runs but doesn't produce heat, here's what might be wrong and when to call for help.

    Get Same-Day Diagnosis (516) 259-1191

    Common Causes & Solutions

    Thermostat Set to FAN Only

    DIY Fix

    The fan is running continuously but the heating cycle isn't activated.

    Solution: Switch thermostat from 'FAN' to 'AUTO' and set to heating mode.

    Clogged Air Filter

    DIY Fix

    Restricted airflow causes overheating and safety shutdown.

    Solution: Replace the air filter with a new one of the correct size.

    Pilot Light or Ignition Problem

    Call Pro

    The burners aren't igniting to heat the air.

    Solution: Professional diagnosis of ignition system required.

    Gas Supply Issue

    Call Pro

    Gas valve closed or gas supply interrupted.

    Solution: Check gas valve position; call professional if issue persists.

    Flame Sensor Dirty

    Call Pro

    Dirty sensor can't detect flame, causing safety shutdown.

    Solution: Professional cleaning or replacement of flame sensor.

    Overheating and Limit Switch Tripped

    Call Pro

    Safety switch shut down burners due to overheating.

    Solution: Professional diagnosis to identify overheating cause.

    When to Call a Professional

    • DIY fixes didn't resolve the issue
    • You smell gas near the furnace
    • Error codes are displayed
    • Problem keeps recurring
    • Furnace is making unusual noises

    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
    (516) 259-1191

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