Furnace Repair & Maintenance

Stay Warm All Winter with Reliable Furnace Maintenance. Your furnace is a crucial part of your home’s heating system. We provide servicing, repairs, and new installations to keep your furnace running efficiently.


Our Furnace Services:

  • Comprehensive furnace inspections
  • Repairs and parts replacement
  • New high-efficiency furnace installations
  • Seasonal maintenance for optimal performance


Schedule your furnace service at least once per year!

Common Furnace Issues and How to Prevent Them

Your furnace is essential for keeping your home warm during the colder months, but like any heating system, it can develop issues over time. Regular maintenance and early detection of problems can prevent costly breakdowns, improve efficiency, and extend your furnace’s lifespan.

Below are some of the most common furnace problems homeowners face and how to prevent them.


1. Furnace Blowing Cold Air


Possible Causes:

  • Dirty Air Filter – A clogged filter can restrict airflow, causing the heat exchanger to overheat and shut down the burner.
  • Pilot Light or Ignition Problems – If your pilot light is out or the ignition system fails, the furnace won’t generate heat.
  • Thermostat Issues – Incorrect settings or a faulty thermostat may prevent the furnace from properly cycling.


How to Prevent It:

  • Replace air filters every 1-3 months to ensure proper airflow.
  • Check the thermostat settings and ensure it’s in “heat” mode.
  • Schedule annual furnace maintenance to inspect the ignition system and burners.


2. Furnace Keeps Turning On and Off (Short Cycling)


Possible Causes:

  • Dirty or Clogged Filter – Restricted airflow forces the furnace to overheat and shut off prematurely.
  • Incorrectly Sized Furnace – A furnace that’s too large for your home will cycle too frequently, reducing efficiency.
  • Blocked or Dirty Flame Sensor – A flame sensor covered in dirt or soot may fail to detect a flame, causing the furnace to shut down.


How to Prevent It:

  • Ensure regular filter replacements to prevent overheating.
  • Schedule a professional furnace inspection to check for sensor or system malfunctions.
  • Install the right-sized furnace to match your home’s heating needs.

3. Furnace Won’t Turn On


Possible Causes:

  • Tripped Circuit Breaker – Electrical issues can prevent the furnace from starting.
  • Malfunctioning Thermostat – A dead battery or wiring issue can cause communication failures.
  • Gas Supply Issues – If the gas valve is closed or there’s a supply issue, the furnace won’t ignite.


How to Prevent It:

  • Check your thermostat settings and replace the batteries regularly.
  • Ensure the circuit breaker hasn’t tripped.
  • Schedule routine furnace inspections to detect gas valve or ignition issues early.


4. Weak or No Airflow from Vents


Possible Causes:

  • Clogged Ducts or Vents – Dust and debris in the ductwork can restrict airflow.
  • Blower Motor Issues – A failing blower motor can reduce airflow efficiency.
  • Dirty Air Filter – A clogged filter reduces the furnace’s ability to push warm air through your home.


How to Prevent It:

  • Clean and inspect ductwork annually for dust, mold, or debris buildup.
  • Schedule routine blower motor maintenance to check for wear and tear.
  • Replace air filters frequently to maintain strong airflow.


5. Unusual Furnace Noises (Banging, Rattling, or Whistling)


Possible Causes:

  • Loose Components – Loose screws, blower belts, or panels can create rattling noises.
  • Expanding and Contracting Ductwork – Temperature fluctuations cause duct materials to expand and contract, creating popping sounds.
  • Ignition Delays – If you hear a loud boom when the furnace starts, gas buildup from a delayed ignition may be the cause.


How to Prevent It:

  • Tighten loose screws and check for unsecured components.
  • Schedule a professional inspection to diagnose and fix ignition delays.
  • Keep ducts clean and properly insulated to minimize temperature-related expansion noises.


6. Yellow Pilot Light Instead of Blue


Possible Causes:

  • Carbon Monoxide Presence – A yellow flame may indicate incomplete combustion and potential carbon monoxide leaks.
  • Dirty Burner – Soot or debris buildup on the burner can alter the flame color.


How to Prevent It:

  • Regularly check the pilot light—it should always burn blue.
  • Have a professional technician inspect the burner and gas supply annually.
  • Install a carbon monoxide detector near the furnace for safety.


7. High Energy Bills with No Change in Usage


Possible Causes:

  • Dirty Filters or Clogged Ducts – A restricted airflow system requires more energy to heat your home.
  • Aging or Inefficient Furnace – Older units require more fuel to produce the same amount of heat.
  • Leaks in Ductwork – Air leaks reduce heating efficiency, causing the furnace to work harder.


How to Prevent It:

  • Upgrade to a high-efficiency furnace if your unit is over 15 years old.
  • Seal and insulate ductwork to improve airflow efficiency.
  • Perform seasonal maintenance to keep your system running smoothly.


8. Burning Smell or Unusual Odors from Furnace


Possible Causes:

  • Dust Burning Off – If you smell burning when you first turn on the furnace for the season, it’s likely dust burning off.
  • Electrical Issues – A burning plastic smell could indicate wiring problems.
  • Gas Leaks – A sulfur or rotten egg smell signals a natural gas leak.


How to Prevent It:

  • Clean around and inside the furnace before the heating season starts.
  • If you smell gas, turn off the furnace immediately and contact a professional.
  • Schedule regular electrical inspections to detect wiring issues early.


How Regular Maintenance Prevents Furnace Issues

Routine furnace maintenance helps detect and fix minor issues before they turn into costly repairs or system failures. Here’s what a professional tune-up includes:


  • Cleaning and inspecting the burner, heat exchanger, and ignition system.
  • Checking for gas leaks, carbon monoxide, or ventilation issues.
  • Testing and calibrating the thermostat for accuracy.
  • Lubricating blower motors and moving parts to prevent breakdowns.
  • Inspecting and replacing filters for better airflow and efficiency.


Scheduling annual furnace maintenance ensures your system remains reliable, safe, and energy-efficient.



WE KNOW HOW TO DO IT

Frequently Asked Questions for Furnace Repair & Maintenance

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  • Why is my furnace blowing cold air?

    Your furnace may be blowing cold air due to:

    • A dirty air filter restricting airflow.
    • A faulty thermostat sending incorrect signals.
    • Ignition or pilot light failure preventing heat production.
    • A clogged condensate line causing the system to shut down.

    Regular maintenance and timely filter changes help prevent this issue. If the problem persists, schedule a professional furnace inspection.

  • How often should I service my furnace?

    It is recommended to schedule furnace maintenance at least once per year, preferably in the fall before winter begins. Regular servicing ensures:

    • Efficient heating and lower energy bills.
    • Fewer unexpected breakdowns.
    • A longer furnace lifespan.

  • What are the signs that my furnace needs repairs?

    Common signs include:

    • Uneven heating or weak airflow from vents.
    • Frequent cycling (turning on and off too often).
    • Unusual noises like banging, whistling, or rattling.
    • A sudden increase in energy bills.
    • A yellow or flickering pilot light (should be blue).

    If you notice any of these issues, schedule a repair before it leads to a costly breakdown.

  • How long does a furnace typically last?

    A well-maintained furnace can last 15 to 20 years. Signs that it’s time for a replacement include:


    • Frequent, expensive repairs.
    • Uneven heating and comfort issues.
    • Rising energy bills due to inefficiency.

    Upgrading to a high-efficiency furnace can save you money in the long run.



  • Why is my furnace making strange noises?

    Unusual sounds often indicate:


    • Banging or popping – Could be air ducts expanding or a delayed ignition issue.
    • Rattling or vibrating – Loose panels, screws, or motor components.
    • Whistling or hissing – Possible airflow restriction or ductwork leaks.

    A professional inspection can diagnose and fix the issue before it worsens.

  • How can I improve my furnace’s efficiency?

    • Replace air filters every 1-3 months.
    • Schedule annual tune-ups.
    • Seal duct leaks to prevent heat loss.
    • Install a programmable thermostat.
    • Ensure vents and registers are not blocked.

    These steps help lower energy costs and extend your furnace’s lifespan.

  • What should I do if my furnace won’t turn on?

    Try these troubleshooting steps:


    • Check the thermostat settings and battery.
    • Ensure the circuit breaker hasn’t tripped.
    • Inspect the furnace filter—a clogged filter can cause shutdowns.
    • Look for a pilot light or ignition issue.

    If the furnace still won’t start, contact Stronghold Plumbing & Gas for professional diagnostics.

  • Is it worth repairing an old furnace, or should I replace it?

    Vented (Direct Vent): Uses an external vent, offering clean indoor air and high efficiency.


    Ventless: No external venting required but must be used in well-ventilated rooms to avoid moisture buildup.If your furnace is over 15 years old and repair costs exceed 50% of a new unit, replacement is the better long-term investment. New high-efficiency furnaces offer:

    • Lower energy bills.
    • Better heat distribution.
    • Fewer repairs and breakdowns.

  • Why does my furnace smell like burning when I turn it on?

    • A dusty smell is normal when turning the furnace on for the first time in the season.
    • A burning plastic or electrical smell could indicate wiring issues—turn off the furnace and call a technician.
    • A rotten egg smell signals a gas leak—shut off the gas and call emergency services immediately.

  • Does Stronghold Plumbing & Gas offer emergency furnace repairs?

    Yes! We provide fast, same-day emergency furnace repairs to restore heat quickly and prevent further damage. Call us anytime for urgent service.