Why is my furnace running but not heating my house?
Common causes are a clogged filter, a thermostat problem, or a weak ignition or blower. Try the quick checks first. If the air stays cold, ask a local provider to inspect the system.
A furnace rarely quits without a hint. You may hear a new rattle, notice uneven heat, or see the bill creep up. Those small changes are worth a look. Catch it early, and a minor fix often stays minor.
Realisesource Heating & Air is a referral service. We do not repair furnaces. We connect homeowners in the Dearborn area with independent providers in our network who handle heating and cooling work. Here you can learn the signs, find out what a visit looks like, and see typical costs. Then you can take a calm next step with a provider who can look at your system and give you a clear, written quote.
Smell Gas? Put Safety First
A rotten-egg smell is the one sign that cannot wait. Stay calm and act in this order.
Leave the house with everyone inside. Do not touch light switches, use a lighter, or make calls while you are still indoors. Once you are outside and away from the home, call your gas utility or emergency services. Wait until they say it is safe before you go back in.
A furnace provider can help later. Safety comes first.
Carbon Monoxide Is Silent
Carbon monoxide has no smell. A cracked part or a blocked vent can let it into the home. Headaches, dizziness, nausea, or a alarm that sounds are all warnings. Get outside into fresh air and call emergency services. Test your alarms each season, especially before the cold sets in.
No Heat on a Frosty Night
Losing heat in deep frost is stressful, and it is fine to feel worried. Close doors to unused rooms. Pull out extra blankets. Keep an eye on bare pipes in basements and crawl spaces, since cold can reach them in an older frame house.
Then take one calm step. Request a callback to check provider availability. Many providers can respond quickly when a home has no heat.
Quick Checks Before You Call Anyone
Sometimes the cause is small. These checks are safe for most homeowners and take a few minutes.
- Set the thermostat to heat and raise it a few degrees. Replace dead batteries if it uses them.
- Check that the furnace switch is on and the breaker has not tripped.
- Look at the air filter. A clogged one can make a furnace shut itself off.
- Make sure vents and returns are open and not blocked by furniture.
- Confirm the gas valve to the furnace is open.
Know When to Stop
Do not open the burner area or try to relight a pilot you are unsure about. Do not reset the same breaker again and again. If a check does not help, stop and ask a provider to take over.
Catch It Early: Signs Your Furnace Needs Repair
Small changes often show up weeks before a breakdown. Spotting them is the easiest way to avoid a big repair.
Sounds That Are New
Banging, squealing, rattling, or a loud hum can point to a worn belt, a loose part, or a motor under strain. A furnace should sound steady. If it changes, take note.
Smells and Sights
A dusty, burning smell on the first cold day is common and often fades. A smell that lingers is not normal. Yellow or flickering burner flames, soot, or moisture near the unit are worth a visit.
Uneven Heat and Rising Bills
Cold rooms, short bursts of heat, or a furnace that keeps turning on and off can mean airflow or ignition trouble. A bill that climbs with no change in habits is another quiet hint.
What Happens During a Furnace Repair Visit
Knowing the steps can ease your mind. Visits vary by provider, but many follow a similar path.
The provider asks what you have noticed, then checks the thermostat, power, filter, and airflow. Next they look at the ignition, burners, flame sensor, and venting. They test safety controls and tell you what they found in plain words.
A good provider explains the fix and gives a written quote before starting work.
Common Furnace Repairs
Ignition and Sensor Fixes
A dirty flame sensor or a worn igniter is a frequent reason for no heat. These parts are often small and quick to swap.
Blower and Motor Work
The blower moves warm air through your ducts. Worn bearings, a weak capacitor, or a failing motor can cause noise or weak airflow.
Control and Safety Parts
Thermostats, circuit boards, pressure switches, and limit switches keep the system safe. When one fails, the furnace may shut down on purpose.
Repair or Replace Your Furnace?
This is a big question, so take your time. A repair often makes sense when the system is not old and the problem is a single part.
Replacement may be worth a talk when the furnace is many years old, needs repairs often, or has a cracked heat exchanger. A cracked heat exchanger can be a safety issue, so a provider should confirm it.
Weighing the Choice
Ask the provider to compare the cost of repair with the cost of a new unit. Also ask how the repair might affect heating bills.
Furnace Replacement Near Me
If you search for furnace replacement near me, you will see many names. Request an estimate from a provider in our network. Compare written quotes, not just prices, and ask about size, efficiency, and installation steps.
Questions to Ask the Provider
A few plain questions help you feel in control. Ask these before work begins.
- What do you think caused the problem?
- Is this a repair, or should I think about replacing?
- What does the written quote include, parts and labor?
- Is there a warranty on the parts or the work?
- How can I spot this problem sooner next time?
Fix It, Then Protect It
Once your heat is back, a little upkeep keeps trouble away. This is where early signs pay off.
Simple Habits That Help
Change the filter on the schedule your provider suggests. Keep vents clear. Clear snow and ice from outdoor vent pipes during winter. Test your carbon monoxide alarms each season.
Book a Yearly Tune-Up
A yearly HVAC service visit before winter lets a provider clean, test, and catch worn parts early. Fall is a good time, before the first deep frost arrives.
Request a callback to ask a provider about a tune-up or a repair visit.
What's Included
Safety Checks
Providers check burners, venting, and safety controls so the furnace runs safely, not just warmly.
Clear Diagnosis
A provider finds the cause and explains it in plain words before work begins.
Written Quote
You get the price in writing first, so you can decide with a calm head.
Upkeep Advice
After the fix, many providers share simple filter and tune-up tips that help prevent the same problem again.
Typical Furnace Repair Costs
Prices vary by home, parts, and the provider. These are typical U.S. ranges only. Always ask for a written quote that lists parts and labor before you agree to any work.
| Item | Typical range | Notes |
|---|---|---|
| Diagnostic visit | $75 – $200 | Often applied toward the repair if you proceed |
| Flame sensor or igniter | $100 – $400 | Common cause of no-heat calls |
| Thermostat repair or swap | $100 – $350 | Depends on basic or smart model |
| Blower motor or capacitor | $150 – $1,000 | Motor replacement sits at the high end |
| Control board | $300 – $900 | Varies by furnace brand and age |
| Furnace replacement | $3,500 – $10,000 | Size, efficiency, and ductwork change the total |
How It Works
Check for Safety
If you smell gas or hear a carbon monoxide alarm, get outside and call emergency services first.
Try Quick Checks
Look at the thermostat, breaker, filter, and vents. Stop if anything feels unsafe.
Reach a Provider
Request a callback or send the request form to connect with a local provider.
Review the Written Quote
Read the quote, ask your questions, and choose the repair that fits your home.
Why Call Realisesource Heating & Air
A Calm Place to Start
Heating trouble is stressful. This page gives you clear steps so you know what to do next.
Independent Providers
You connect with local providers in our network who do the actual work.
Early Warning Focus
We help you spot small signs so minor problems stay small.
No Obligation
Ask questions and request an estimate without any pressure to commit.
Other Services
Need furnace repair in Dearborn?
Tell us what your system is doing and where you are. We will point you toward a local provider in our network, with no obligation.
No obligationQuestions
Furnace Repair FAQ
Is it safe to keep using a furnace that makes strange noises?
Not always. Loud banging or squealing can mean a failing part. If you smell gas or a carbon monoxide alarm sounds, leave and call emergency services. Otherwise, turn it off and ask a provider.
How often should a furnace be serviced?
Most providers suggest a tune-up once a year, ideally in the fall before cold weather arrives. Regular visits help catch worn parts early and keep your heating and cooling running steadily.
Contact
Reach a local provider
Tell us what your system is doing and where you are. We will point you toward a local provider in our network, with no obligation.
No obligation