Do you hear something? When to investigate strange household noises

Houses can talk. Not with words but with the soft rumble of a furnace, the tapping of pipes as they expand and contract, or the creak of floorboards under your feet. Most of these household noises are benign; in older homes, they might add some character. But there are a handful of sounds that might spell trouble.

* Clanking when you turn on the heat.
Groaning pipes are normal when you switch on the heat for the first time each fall, as are taps and clinks if you have baseboard heat. But knocking or clanking sounds could signify that your circulator pump is about to fail. Call a licensed HVAC technician right away.

* Whistling windows.
Sub-par installation, wear and tear, or temperature changes can create whistling sounds around your windows and might signify wasted energy. If you’re very handy, you might be able to find the problem and fix it yourself — otherwise, call a professional. Repair costs are likely cheaper than increased energy bills over time.

* Hissing sounds.
If you hear a hiss every time your HVAC system switches on, you may have a leak at the compressor, radiators, or air ducts, which a licensed technician can identify and repair. If your home has natural gas, you may have a leak. If you hear the hiss and smell gas, evacuate the house immediately and call the gas company — don’t try to shut off the gas yourself.

* Bubbling noises in the water heater.
Bubbling or cracking noises in a gas-fired water heater comes from sediment in the bottom of the tank, which builds up over time and bubbles in the heat. If you already hear the noises, your tank might be nearing the end of its lifespan. Draining the tank may help it last longer, but it won’t reverse the damage. Make sure to drain any gas-fired water heater every few months to prevent sediment buildup and extend its lifespan.