How loud should a new furnace be?

A new furnace should be very quiet — noticeably quieter than older models. Most homeowners are pleasantly surprised by how silent modern high-efficiency furnaces are during normal operation.

What's Normal

A properly installed new furnace will produce a low, steady hum when the blower is running, and a soft whoosh of air through the vents. You might hear a gentle click when the burner ignites, followed by a brief rush of air as the system comes up to speed. High-efficiency two-stage and variable-speed furnaces are especially quiet, as they often run at lower capacity for longer cycles rather than blasting on and off repeatedly.

In terms of decibels, modern furnaces typically operate in the 50–65 dB range — roughly comparable to a quiet conversation or a running refrigerator. Variable-speed models can be even quieter at low-stage operation.

Ottawa-Specific Context

In Ottawa's cold climate, your furnace works hard — especially during those -20°C January nights. A properly sized and installed unit should still run quietly even under heavy load. If your new furnace seems loud from day one, it's worth having the installer check the duct sizing and static pressure, as undersized ductwork is a common cause of excessive noise in Ottawa homes.

Sounds That Are Never Normal on a New Furnace

Even on a brand-new unit, call your technician if you hear any of the following: banging or booming on startup (could indicate delayed ignition), rattling or vibrating panels, high-pitched squealing, or rumbling during the burner cycle. These are not break-in noises — they indicate something needs attention.

Safety Note

A booming or loud bang on ignition is worth taking seriously, as it can indicate a gas buildup before ignition — a condition that should be inspected promptly by a licensed technician.

If your new furnace is louder than expected, don't just live with it. Ottawa HVAC Pro can assess whether it's an installation issue, ductwork problem, or equipment defect. Request a quote or consultation and we'll make sure your system is running as quietly and efficiently as it should be.