When your furnace stops working, it can get uncomfortable fast, especially during a cold Treasure Valley winter. Before you assume the worst, there are a few simple things homeowners can check. Some furnace problems have quick fixes. Others need professional help from a trusted local company like Diamond Heating and Cooling.
This guide covers common furnace issues, what you can safely check at home, and when to call for service in the Boise area.
Start with the thermostat
It sounds simple, but many furnace calls start with thermostat issues.
Check that:
The thermostat is set to “heat”
The temperature is set higher than the room temperature
The batteries are not dead
The screen is working
If the thermostat is not working properly, the furnace may not turn on at all.
Check the air filter
A dirty air filter is one of the most common reasons a furnace stops working well. When the filter gets clogged, airflow is blocked. This can cause the furnace to overheat and shut down.
Pull out your filter and take a look. If it looks dusty or gray, replace it. Most homes should change filters every 1 to 3 months during the heating season.
Look at the power
If the furnace will not turn on, check the power source.
Make sure the furnace switch is on
Check the breaker panel for a tripped breaker
Confirm the furnace door is fully closed
Many furnaces have a safety switch that prevents them from running if the panel is not secure.
Check the vents and registers
Blocked vents can cause uneven heating or make it seem like the furnace is not working.
Walk through your home and make sure:
Vents are open
Furniture is not blocking airflow
Return air vents are clear
Good airflow helps the furnace run safely and efficiently.
Listen for unusual sounds
Your furnace should run fairly quietly. If you hear loud banging, rattling, or squealing, something may be wrong. These sounds can signal loose parts, motor issues, or airflow problems. If you hear anything unusual, it is best to turn the system off and call a professional.
Watch for warning signs
Call for service if you notice:
Furnace blowing cold air
System turning on and off often
Burning smells that do not go away
Rising energy bills
Uneven heating in your home
Furnace not turning on at all
These signs can point to deeper issues that need professional tools and training.
Why professional service matters
Modern furnaces have safety systems and complex parts. While homeowners can check simple things like filters and thermostats, deeper repairs should always be handled by a licensed technician.
Regular maintenance can prevent many furnace problems before they start. Annual tune ups help keep systems running safely and can extend the life of the furnace.
Why choose Diamond Heating and Cooling
Diamond Heating and Cooling has helped many Boise homeowners keep their homes warm and comfortable. Their technicians understand local winters and the common furnace issues in this area.
Homeowners trust them because they offer:
Experienced local technicians
Honest pricing and clear communication
Fast response during cold weather
Heating, cooling, plumbing, and electrical services
Having one reliable company for home services makes it easier to keep your home running smoothly all year.
A furnace that is not working can be stressful, but many issues have simple solutions. Checking the thermostat, filter, and power can sometimes get your system running again. If the problem continues, calling a trusted professional is the safest next step.
Diamond Heating and Cooling is ready to help Boise homeowners with furnace troubleshooting, repairs, and maintenance so your home stays warm all winter long.