Sweater season is here! That means cozying up with a blanket to watch the Denver Broncos game or enjoying family game nights with hot cocoa. But if your furnace isn’t working, you’ll need more than a blanket to stay warm and comfortable on cold Colorado winter evenings.
In my 10+ years as an HVAC technician, I’ve seen all kinds of unexpected, costly emergencies, many of which could have been prevented. In this article, I’ll cover the most common issues and how you can avoid furnace problems in the chilly months ahead.
Table of Contents
- Signs of Furnace Problems
- 5 Common Furnace Problems in Westminster Homes
- Annual Furnace Maintenance in Westminster, CO
- Westminster Furnace Problems FAQs
Signs of Furnace Problems
Colorado homeowners rely on their heating systems for safety and comfort, so it's crucial to stay aware of potential issues and take proactive steps to address them.
Here are furnace problem signs you don’t want to ignore:
- Higher-than-usual energy bills
- Cool air is coming from the vents
- Difficulty starting or frequent cycling
- Inconsistent heating or cold spots
- Strange noises and odors
If you notice any of these signs, call L&M HVAC. With prompt response, we can often prevent these problems from turning into full-system breakdowns.
Tech Tip: If you’re experiencing furnace problems and your system is 10+ years old, replacement with a newer, high-efficiency system might be more economical than fixing an aging system.
Here are 5 common furnace problems we see and what to do about them:
Top 5 Types of Furnace Problems
1. Dirty or Clogged Air Filters: A Common Furnace Problem
Dirty air filters are among the most common problems we see, but they’re also one of the most preventable. A dirty air filter makes your heater work harder to draw air into its components, raising utility bills, adding wear and tear on your system, and even causing it to shut down.
Signs of a dirty furnace air filter:
- Reduced airflow
- Dusty house
- Strange noises
- Allergies
Regularly replacing your air filter is a cheap and easy way to increase efficiency and extend its lifespan.
If you notice any of the above symptoms, check your air filter first. If the problems persist, there may be a bigger issue.
Tech Tip: Swap out air filters every 1-3 months for optimal performance, maximum efficiency, and improved indoor air quality.
2. Blower Motor Problems That Affect Furnace Performance
Your furnace’s blower motor powers warm airflow, ensuring even heating throughout your home.
Signs your furnace blower motor is failing:
- Fraying or cracks on the fan belt
- Belt slipping
- Sudden system shutdown
- Short cycling (turning off before it’s reached its desired temperature)
- Odd sounds (squealing, scraping, squeaking)
3. Cracked Heat Exchangers: One of the Most Serious Furnace Problems
The heat exchanger transfers heat from the combustion flame to the air circulating through your home. Its sealed chamber prevents harmful gases, like carbon monoxide, from mixing with indoor air, ensuring safe, efficient heating.
Warning signs of a cracked heat exchanger:
- Strange smells
- A yellow, flickering flame
- Unusual noises like popping or rattling
- The carbon monoxide detector is going off
If you suspect a cracked heat exchanger, call your HVAC provider immediately. A cracked heat exchanger can introduce carbon monoxide into your home – a severe safety issue for you and your family.
Tech Tip: A failing heat exchanger can often be caught during routine check-ups. Schedule planned maintenance to keep your system running smoothly – and safely – all winter.
4. Thermostat and Temperature Control Furnace Problems
Modern thermostats make home comfort easy and convenient – they communicate with your furnace to keep your home warm. But if yours fails, your furnace can’t keep your home warm.
Signs your furnace thermostat isn’t working:
- Inconsistent temperatures
- Frozen or unresponsive display
- No power to the thermostat
- Short cycling
- Constantly cycling fan
If you notice any of these problems, the fix could be as simple as replacing your thermostat batteries. If you change your batteries and the problem persists, it could be a power supply or electrical issue. Give L&M HVAC a call; we know how to safely assess electrical components and get your system running smoothly again.
Tech Tip: Replace your thermostat batteries once a year to prevent future issues
5. Ignition or Pilot Light Issues That Prevent Your Furnace From Heating
The pilot light (sometimes called the ignition control or ignitor) is one of the most essential components of your furnace. It produces a flame that converts natural gas to heat. If that flame isn’t lit, your furnace cannot produce heat.
Common signs of ignition or pilot light failure:
- Gas smell
- Lack of heat
- Strange noises
- Frequent cycling
If you suspect a pilot light issue, check the flame on your furnace (usually located at the bottom of the furnace, behind the access panel).
If it’s functioning correctly, the flame is blue with a slightly yellow tip. If it’s red, yellow, or any color other than blue, evacuate your home and contact an HVAC professional immediately.
Tech Tip: Never try to fix your pilot light alone. Though a faulty pilot light is easy to recognize, it isn’t easy to fix. Without the help of an experienced technician, burns or other serious injuries could result.
Annual Furnace Maintenance: The Best Way to Prevent Furnace Problems in Westminster
Though a poorly running furnace is typically easy to spot, fixing it can be another story. With Front Range winter temperatures often dipping below 0℉, minor furnace issues can quickly become emergencies.
With regular maintenance and care, you can often prevent these common furnace problems.
Scheduled maintenance with L&M HVAC:
- Prevents costly repairs & breakdowns
- Keeps your home safe
- Reduces energy costs
Our thorough tune-ups include a 21-point inspection. We cycle your furnace, conduct a detailed assessment, and provide a comprehensive report that addresses outdated components and any issues that could cause inefficiency, safety concerns, or property damage. Our technician offers transparent, honest recommendations for addressing issues – never pushing unnecessary upgrades.
L&M HVAC: Westminster’s Trusted Furnace Experts
Whether your furnace needs routine maintenance, a fast repair, or is nearing the end of its lifespan, L&M HVAC’s experienced team provides honest guidance and reliable solutions tailored to your home.
Contact L&M HVAC today to schedule furnace service in Westminster and surrounding Front Range communities.
Westminster Furnace Problems FAQs
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L&M HVAC provides quality residential HVAC services to Westminster and the surrounding Metro Denver Region.
Emergency service is available.
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