Furnace Won’t Start: DIY Checks vs. When to Call a Professional
When the weather is chilly and Santa Ana winds are blowing, you don’t want to deal with a furnace that won’t start. There are many different reasons why a furnace could malfunction, which is why a proper diagnosis is important.
To ensure the safety and comfort of your family, you need the help of a professional heating, ventilation, and air conditioning (HVAC) technician. At Fox Family Heating & Air Conditioning, our leading HVAC experts can help you determine why your furnace isn’t working and the necessary steps for fixing it.
Common Reasons a Furnace Won’t Start
As a homeowner, it can be challenging to figure out why a furnace is not turning on. There can be multiple reasons for this malfunction, which is why a professional HVAC inspection is essential. In most cases, furnaces won’t start due to one of the following issues.
- Thermostat Settings: If your thermostat is set to “cool” or “fan only,” you won’t feel any heat. Additionally, a malfunctioning thermostat may be unable to trigger the heat to turn on.
- Dead Batteries: When the batteries are dead in your thermostat, it stops the thermostat from turning the furnace on.
- Clogged Air Filters: Sometimes, air filters can become so clogged that the furnace overheats. When this happens, the furnace automatically switches off to protect the furnace and your home from potential harm.
- Tripped Breakers: Breakers trip as a safety mechanism. Once they are switched off, electricity can’t flow through the wiring to your furnace.
- Dirty Flame Sensors: If the burner flame sensor is dirty or not working properly, it won’t be able to sense when the burner is lit. When this happens, it will automatically trigger the system to shut off.
- Safety Switch Triggered: Any time a pressure or limit switch is triggered, it can result in your furnace shutting off. Because this indicates that there is an underlying safety problem, you should always call an HVAC technician for furnace maintenance.
- Gas Supply Issues: If a gas furnace won’t start, it may be due to problems with the gas supply. This is another potentially dangerous issue, so schedule a professional HVAC inspection right away.
- Unit Age or Component Wear: As furnaces age, they become less efficient and components can wear down. Eventually, this can lead to problems starting and other performance-related issues.
DIY Checks You Can Safely Try
So, why won’t my furnace turn on? If you don’t hear your furnace switch on, there are a few common reasons why. The following furnace troubleshooting steps can help you figure out the source of the problem. For more advanced furnace repairs, you should always reach out for professional help.
Check the Thermostat
If your furnace won’t kick on, start by checking the thermostat. Make sure it is in “heat” mode. Then, increase the temperature so that it is higher than your current room temperature. This should trigger the furnace to kick on. If it doesn’t, you should also try replacing the batteries.
Check the Furnace Switch & Breaker
Next, you can try troubleshooting your furnace switch. Start by locating the furnace switch, which is often on the side of the furnace. It should be in the “on” position. You should also check the breaker panel and reset tripped breakers.
Check Your Air Filter
Clogged air filters can prevent airflow and cause your unit to overheat. Once this happens, the furnace will shut off as a safety mechanism.
Fortunately, you can easily prevent this problem by cleaning or replacing your air filter. Most manufacturers recommend changing the air filter every 30 to 90 days. However, filter changes should be done more often during periods of peak usage.
Make Sure the Furnace Door Is Closed
If the furnace door is open, the safety switch can prevent it from starting. To troubleshoot this issue, close the furnace door.
Check the Pilot Light
If your furnace has a pilot light, a faulty pilot light can prevent your furnace from starting. To check for this problem, find and observe the pilot light. It should have a steady, blue flame. If the flame is yellow or flickering, this indicates incomplete combustion.
Relighting the pilot light and troubleshooting pilot light issues aren’t DIY tasks. When the pilot light is responsible for your furnace problems, you should always reach out for expert help.
Look for Error Codes
Your furnace’s manual or the diagnostic code table on the control panel should list what blinking lights mean. While different blink quantities represent different problems according to each brand, the following are the most common meanings.
- 1 Flash: Ignition-related problems
- 2 Flashes: Pressure switch stuck closed
- 3 Flashes: Pressure switch stuck open
- 4 Flashes: Open high limit
- 5 Flashes: Flame sensor issues
Warning: DIY Checks You Should Avoid
When a heater won’t start, there are a few DIY checks you can do to narrow down the source of the malfunction. If the previous troubleshooting steps are ineffective, do not try to repair your furnace on your own. HVAC systems are extremely complex, so DIY repairs can lead to physical dangers to yourself and your unit.
You should never do any of the following repairs on your own.
- Opening any gas components or lines
- Removing or cleaning the flame sensor
- Repairing, replacing, or updating any wiring
- Resetting limit switches
- Working on capacitors
- Disassembling interior components
Trying to perform these tasks on your own can lead to gas leaks, electric shocks, carbon monoxide poisoning, and damaged HVAC components. Rather than risk these potential issues, give Fox Family a call for help with all of your furnace replacements and repairs.
When To Call a Professional HVAC Technician
At Fox Family Heating & Air, we have years of experience in helping residents with all of their HVAC installations and repairs. While there are some problems you can handle on your own, there are situations where delayed repairs can risk the safety, health, and well-being of your home and family. The following are some of the major red flags that indicate your furnace requires professional help.
- Furnace Keeps Cycling But Never Starts: Often, this problem is related to the control board or ignition system. These are both tasks that are best left to the experts.
- Repeated Breaker Trips: A breaker might trip once because of a random power fluctuation. If the same breaker trips repeatedly, there is an underlying issue with your electrical system that needs to be repaired.
- Gas Smells: Gas odors are an immediate danger to yourself and your family. As soon as you smell gas, switch off the furnace and exit your home. Then, call your gas utility provider for help. The utility provider can switch off the gas to prevent a fire, gas poisoning, or explosion. Afterward, one of our HVAC technicians can inspect your furnace and determine the underlying cause of the problem.
- Error Codes Persist: Understanding the manufacturer’s error codes requires specialized knowledge, equipment, and skills.
- Furnace is 12 to 15 Years Old: Once your furnace is 12 to 15 years old or older, it is more likely to break down. It also becomes less efficient, so your energy bills will increase. To save money over the long run, the best option is to get a new furnace installation.
- DIY Checks Didn’t Work: If your DIY troubleshooting tips didn’t fix the problem, a serious issue is likely at fault. To remedy the problem, you need to reach out for professional help.
Knowing when to call an HVAC technician is important for your comfort and peace of mind. When you call Fox Family, one of our team members will quickly come to your home to evaluate your furnace and test for performance issues. Then, our team will give you an honest recommendation about the best repairs and maintenance options for your needs. We’re here to serve as your trusted advisors, so we never pressure you into any services.
Why Choose Fox Family Heating & Air Conditioning
If your furnace won’t start, Fox Family is the place to go for time-tested, locally trusted repair services. Sacramento homeowners turn to us for several key benefits.
- Highly Trained Technicians: Our respectful, experienced technicians are highly trained, so you can enjoy the best possible results.
- Fast Response Time to No-Heat Emergencies: When a disaster strikes, you can’t wait around for HVAC services. We offer fast, 24/7 repairs, so you can get help as soon as you need it.
- Local, Family-Owned Business: Our company is family-owned and based in Sacramento, so we understand what local residents need from their heating services.
- Transparent Pricing: Before we begin work, we will always review pricing upfront so that you know exactly what to expect.
- Honest Recommendations: At Fox Family, we are committed to being trusted advisors for local homeowners. With this in mind, we always provide honest, no-pressure recommendations.
- Safety Troubleshooting: We quickly troubleshoot safety issues, ensuring your family is safe and comfortable.
- Thousands of 5-Star Reviews: Fox Family delivers the top results in the industry, and you don’t have to take our word for it. Our thousands of 5-star reviews show what it’s like to partner with our experienced HVAC team.
Schedule Professional Furnace Repairs and Replacements in Sacramento
Struggling with a furnace that won’t start? Our licensed Sacramento HVAC technicians can quickly diagnose the underlying problem. Give us a call at (916) 877-1577 to request your next service appointment today.
