A direct answer from your local HVAC team
When should you call for furnace repair?
Call for furnace repair when your system stops producing dependable heat, blows cold air, cycles repeatedly, makes new noises, creates unusual odors, or heats the home unevenly. Apple Aire provides furnace diagnosis and repair from its Wheat Ridge location throughout the Greater Denver area, including 24/7 emergency service.
Symptoms and next steps
What should you do when your furnace acts differently?
| What you notice | A sensible next step |
|---|---|
| No heat | Confirm the thermostat is set to heat and the breaker has not tripped. If the furnace still will not start, request service. |
| Cold or weak airflow | Check whether the filter is visibly clogged and make sure supply vents are open. Persistent problems need diagnosis. |
| Short cycling | Frequent starts and stops can involve airflow, thermostat, control, or equipment issues. Avoid repeated resets and schedule an inspection. |
| New banging, rattling, or squealing | Turn the system off if the sound is severe or worsening, then arrange service before continued operation causes more damage. |
| Burning or gas odor | A brief dusty smell at first seasonal startup can occur. For a gas odor, leave the area and contact the gas utility or emergency services from a safe location. |
| Uneven heat or rising bills | Verify vents are open and the filter is clean. Ongoing comfort or energy changes can indicate a furnace, duct, or airflow problem. |
Safety first: If you smell gas or a carbon monoxide alarm sounds, leave the home and contact the gas utility or emergency services from a safe location. Do not remain inside to troubleshoot the equipment.
Make an informed decision
Furnace repair or replacement?
A single problem does not automatically mean that you need a new furnace. The right decision depends on the failed component, equipment condition, repair history, comfort, efficiency, and expected remaining service life.
Repair may make sense when
- The failure is isolated and repairable.
- The furnace has otherwise been dependable.
- Comfort and energy use were acceptable before the problem.
- The repair cost is reasonable relative to the system's condition.
Compare replacement when
- Breakdowns are becoming frequent.
- A major component needs an expensive repair.
- The system still struggles with comfort or efficiency.
- Safety, sizing, or overall equipment condition is a concern.
Apple Aire can explain the diagnosis and help you compare repair with furnace replacement, including current rebate and financing information where applicable.
What to expect
A straightforward furnace service visit
- Describe the problem.Tell our team what changed, when it began, and whether the home has any heat.
- Inspect and diagnose.A technician evaluates the furnace, controls, airflow, and other relevant components.
- Review the finding.We explain the likely cause and the available next steps before work proceeds.
- Repair and confirm operation.After an approved repair, the system is checked for normal operation.
Apple Aire is an independent Lennox dealer and services all major brands of heating equipment. Our team arrives with stocked service vehicles, and many common repairs can be completed during the initial visit when the required part is available.
Homeowner questions
Furnace repair FAQ
What are the most common signs that a furnace needs repair?
Call for service when a furnace stops producing warm air, cycles more often than usual, heats rooms unevenly, makes new noises, produces unusual odors, or causes an unexplained increase in heating costs. A professional diagnosis is the safest way to identify the cause.
Is a furnace that blows cold air always broken?
Not always. A thermostat setting or a recently started heating cycle can briefly produce cool air, but persistent cold air can be related to ignition, airflow, control, or equipment problems. If basic thermostat and filter checks do not resolve it, schedule a professional inspection.
When is a furnace problem an emergency?
Leave the home and contact the appropriate emergency service or gas utility if you smell gas, a carbon monoxide alarm sounds, or you believe combustion gases may be entering the home. Loss of heat during dangerous cold can also require urgent service, especially for vulnerable occupants or at-risk plumbing.
Should I repair or replace my furnace?
Repair can make sense when the furnace is in otherwise good condition and the failure is isolated. Replacement may deserve consideration when breakdowns are frequent, a major repair is needed, comfort or efficiency remains poor, or the equipment is near the end of its expected service life. An inspection provides the information needed to compare both options.
Does Apple Aire repair furnace brands other than Lennox?
Yes. Apple Aire is an independent Lennox dealer and services all major brands of heating equipment, including gas furnaces, throughout Wheat Ridge and the Greater Denver area.
Content reviewed for Apple Aire service accuracy on September 8, 2026. A named technical reviewer will be added after credentials are confirmed.