When cold weather hits, few things are worse than a malfunctioning furnace, leaving you without heat when you need it most. If you’re experiencing issues, there are a few troubleshooting steps you can take to restore warmth while you arrange professional service temporarily. At Carol Flynn Heating & Cooling, Inc., our team specializes in furnace repair and installation in Redwood City, CA, offering expert diagnostics, maintenance, and long-term solutions to keep your system running efficiently. For fast, reliable service, call us at (650) 697-1535, and let our experienced technicians restore comfort to your home.


Redwood City, CA Furnace

Troubleshooting Furnace Problems: DIY Fixes and Expert Solutions for a Warm Winter

1. Check Your Thermostat Settings

Before assuming the worst, verify that your thermostat is turned on and set correctly. Accidental adjustments, wear and tear, or even a slight bump can switch it off. Ensure it is set to “heat” rather than “cool” and that the temperature is set high enough to activate the furnace. To rule out thermostat malfunctions, compare its reading with a separate room thermometer—if the difference is more than 2-3 degrees, the thermostat may need recalibration or replacement. Carol Flynn Heating & Cooling, Inc. can diagnose and recommend smart thermostat options for better control.

 

2. Inspect Your Breaker and Fuses

Power outages, thunderstorms, or ice storms can trip breakers or blow fuses, shutting down your furnace. Locate your electrical panel, typically in the garage or a closet, and check if the breaker is switched off. If unsure, flip it off and back on to reset it. A simple breaker reset can often restore furnace functionality.

 

3. Check and Replace Air Filters

A clogged air filter can restrict airflow, causing the heat exchanger to overheat and shut down the furnace. We recommend changing filters every one to three months to maintain efficiency and prevent costly damage. A dirty filter not only reduces heat output but also shortens your furnace’s lifespan. If you’re unsure how to replace it, consult your furnace’s manual or contact an expert for assistance.

 

4. Verify Gas Supply and Chimney Exhaust Flue

For fuel-powered furnaces, confirm that the gas supply is turned on and that the chimney exhaust flue is clear. A blocked flue can cause ventilation issues, preventing proper furnace operation. If you smell gas, do not attempt to fix it yourself—immediately turn off the gas supply and evacuate.

 

5. Flush Drain Lines and Check Ductwork

Over time, drain lines can become clogged, especially after months of inactivity. Flushing them out can restore proper airflow and drainage. Additionally, blocked or leaky ductwork can prevent warm air from circulating efficiently, increasing energy bills and reducing comfort. Our trusted team can inspect and clear any obstructions for optimal performance.

 

6. Address Gas Leaks Immediately

If you detect a gas smell, take action immediately. Avoid using open flames, matches, or electrical switches. Evacuate your home and, if possible, shut off the gas supply valve located near your gas meter. Once safe, call us for emergency service to handle the issue.

 

When to Call a Professional

If you’ve tried these troubleshooting steps and your furnace is still not functioning properly, it’s time to call the experts at Carol Flynn Heating & Cooling. With over 25 years of experience in furnace repair and installation in Redwood City, CA, they can diagnose issues quickly and recommend whether repair or replacement is the best option. If your furnace is over 10 years old, upgrading to a newer, energy-efficient model could save you hundreds in heating costs annually.

 

Enhancing Home Efficiency with Modern Furnaces

The Need for Energy-Efficient Furnaces

With rising energy costs and environmental concerns, homeowners are focusing on more efficient heating systems. An outdated furnace can waste up to 30% of its energy due to leaks and flue losses. Upgrading to a modern, energy-efficient furnace helps reduce energy waste, lower bills, and maintain home comfort.

 

How Forced-Air Heating Systems Work

Most Bay Area homes use central forced-air heating systems, where air is heated in a metal heat exchanger and distributed through air ducts. A fan pushes warm air into rooms while combustion gases exit through a flue. Older gravity furnaces operate without fans, allowing warm air to rise naturally but at lower efficiency levels.

 

Fuel Choices and Their Impact

Furnaces run on various fuels, including natural gas, propane, oil, electricity, and wood. Natural gas remains the most popular due to its affordability and availability. Forced-air systems are also versatile, allowing integration with air conditioning, humidifiers, and air purifiers.


Understanding Furnace Efficiency Rating

Understanding Furnace Efficiency Ratings

Furnace efficiency is measured using the Annual Fuel Utilization Efficiency (AFUE) rating, indicating the percentage of fuel converted into usable heat. New furnaces range from 78% to 96.7% AFUE, with high-efficiency models exceeding 90%. Investing in a high-efficiency furnace can significantly reduce energy costs over time.


Upgrading to a High-Efficiency Furnace

If your furnace is over 15 years old, it may operate at only 60-70% efficiency, leading to excessive energy waste. Replacing it with a high-efficiency model improves heating performance and reduces monthly bills. Choosing the right furnace size is crucial—too small and it won’t heat effectively, too large and it will cycle inefficiently, increasing wear and tear.


The Role of Air Ducts in Efficiency

Even the most efficient furnace cannot compensate for leaky air ducts, which can cause 20-30% of heat loss. Professional duct sealing and insulation help ensure heated air reaches intended areas without unnecessary loss, improving overall efficiency and comfort.

Choosing a Trusted Furnace Brand

Carrier is a leading furnace brand, known for reliability and high efficiency. Their top models, such as the SXC, achieve AFUE ratings of up to 96.7%, making them an excellent choice for energy-conscious homeowners.


Invest in Energy Efficiency Today

Upgrading your furnace and ensuring proper duct sealing can enhance comfort, reduce energy costs, and contribute to environmental sustainability. If you’re experiencing high energy bills or uneven heating, contact Carol Flynn Heating & Cooling today for a free consultation and start improving your home’s efficiency.

 

Find the Right Furnace for Your Home

Choosing the right furnace is about more than just picking a brand—it’s about selecting the right size and efficiency for your home. Our NATE-certified technicians will evaluate your home’s heating load and recommend the best system within your budget. Bigger isn’t always better, and an improperly sized furnace can lead to inefficiency and higher costs.

 

Stay Warm This Winter

Don’t wait until the cold catches you off guard—trust Carol Flynn Heating & Cooling, Inc. for expert furnace repair and installation in Redwood City, CA to keep your home warm and efficient. Whether you need a quick fix or a brand-new heating system, our experienced team ensures top-quality service and long-lasting solutions. Call us today at (650) 697-1535 to schedule an inspection or consultation and experience reliable, professional HVAC care.

 

Furnace FAQs


How can I prevent my furnace from breaking down?

To minimize the risk of furnace breakdowns, it’s essential to engage in regular furnace maintenance, such as scheduling annual professional inspections and promptly addressing any identified issues. Neglecting routine upkeep can lead to increased energy bills, dangerous breakdowns, and even carbon monoxide poisoning. Additionally, ensuring proper ventilation, sealing air leaks, and keeping vents unobstructed by furniture or drapes can enhance system efficiency. Implementing these measures can help extend your furnace’s lifespan and maintain optimal performance.

What are the benefits of upgrading to a high-efficiency furnace?

Upgrading to a high-efficiency furnace can significantly reduce energy consumption, as these systems convert up to 98% of fuel into usable heat, dramatically decreasing monthly expenses compared to older models. This enhanced efficiency not only lowers utility bills but also minimizes environmental impact by reducing carbon emissions. Additionally, high-efficiency furnaces often feature advanced filtration systems, improving indoor air quality and promoting a healthier living environment. Recognizing signs to install a new high-efficiency furnace, such as frequent repairs or inconsistent heating, can further enhance home comfort and reliability.


Is natural gas or electric heating more efficient?

Upgrading to a high-efficiency furnace improves energy efficiency, lowers heating costs, and reduces environmental impact. With AFUE ratings of up to 98%, these systems convert nearly all fuel into usable heat, making them far more cost-effective than older models. Advanced features like variable-speed blowers ensure consistent temperatures and quieter operation for better home comfort. When preparing your home for a new heating installation, consider potential rebates or tax incentives that can help offset the initial investment.

About Us

Welcome to Carol Flynn Heating & Cooling! Let us design and install a highly efficient heating and cooling system in your home and/or office. Superior products and quality installations for less.

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Carol Flynn Heating & Cooling

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We Service – All SF Bay Area Counties

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