Troubleshooting · 5 min read

What That Noise Means: Common Home System Sounds Explained

Banging or "water hammer" in your pipes

A loud bang when you shut off a faucet or your washing machine stops filling is usually water hammer — a pressure shock when water flow stops suddenly. Occasional water hammer is harmless; frequent or worsening banging can loosen pipe fittings over time and is worth having checked.

Popping or rumbling from the water heater

This is almost always sediment that has settled at the bottom of the tank, trapping water underneath that boils and pops as it heats. It is a sign the tank could use a flush, and if it is happening on an older unit, worth reading up on replacement timing as well.

Squealing from your HVAC system

A high-pitched squeal when your furnace or air handler kicks on is often a worn or slipping blower belt, or a motor bearing that needs lubrication. It is inexpensive to fix early and expensive to ignore, since a failed blower motor is a much bigger repair.

Clicking from the furnace

A few clicks as the igniter fires is completely normal. Repeated clicking without the furnace actually starting usually means the igniter or flame sensor is failing and the unit is trying (and failing) to light.

Gurgling drains

Gurgling in a sink or tub after running a different fixture usually points to a partial clog or a venting issue in the drain line. Occasional and mild is normal; loud and frequent gurgling is worth a closer look before it becomes a full clog.