furnace Repair in AURORA

There are several reasons your furnace may not start. In many cases, the issue is related to the thermostat not sending the correct signal, a tripped breaker, or a safety switch preventing operation. Modern furnaces also have built-in protections that shut the system down if they detect overheating, poor airflow, or flame failure.

Other common causes include:

- A faulty or dirty ignitor

- A malfunctioning limit switch

- An incorrectly positioned furnace door

- A failed control board

If your furnace clicks but doesn’t turn on, or if it’s completely unresponsive, it’s best to have a technician inspect it. Many of these issues can worsen if ignored or repeatedly reset. A quick diagnostic visit usually identifies the exact cause and prevents more expensive repairs down the road.

Furnaces blow cold air when they can’t complete the heating cycle. This often happens when an internal component isn’t operating correctly — like the flame sensor, ignition system, or blower motor. A dirty flame sensor is one of the most common culprits. When coated with soot, it fails to detect the flame and the furnace shuts off the burners while the blower keeps running, pushing cold air through your home.

Other possible reasons include:

- A clogged air filter restricting airflow

- A malfunctioning thermostat

- Low gas supply or gas valve issues

- A cracked or dirty heat exchanger

Furnace overheating and shutting off the burners

If cold air is coming out consistently, shut the system down to prevent damage. A trained technician can clean the components, adjust settings, and restore normal heating performance.

Different noises can indicate different problems. For example:

- Banging or booming often points to delayed ignition, where gas builds up before lighting — this can damage the heat exchanger if left untreated.

- Squealing or screeching usually comes from worn blower belts or failing motor bearings.

- Rattling or vibrating can be caused by loose panels, screws, or components inside the system.

- Grinding noises indicate serious blower motor or cage damage.

Unusual sounds are always a warning sign. Furnaces should operate quietly, and persistent noise usually means a mechanical failure is developing. Early repairs can prevent major component replacements and improve safety.