Water heaters are praised for their longevity. Typical water heaters can last anywhere from 8 to 15 years, depending on their heating method. But what if, out of the blue, your water heater starts to make weird and scary noises? Are water heaters supposed to make noise, anyway?
A functional water heater is nearly silent. The occasional gurgle is perfectly normal, but if it starts making odd popping, screeching, or sizzling sounds, it might be time to take action.
6 Common Water Heater Sounds and Solutions
Table of Contents
To avoid potentially dangerous and expensive plumbing situations, keep an ear out for the following noises:
1. Popping and Rumbling
Popping noises occur when a water heater has an abnormal amount of mineral deposits and sediment at the bottom of the tank.
This usually only happens with older tanks as it takes a while for deposits and debris to collect and stick to the bottom of the water heater.
As the water heats up, deposits ‘crack’, hence the popping noise. Rumbling sounds also occur when said sediments are stirred by the tank’s water. The more the sediment, the louder the sound.
Luckily, there’s an easy solution to this problem. First, you’ll need to drain or flush the water heater. Then, clean the tank by descaling and removing any debris out inside the heater.
Here’s how to drain and descale a water heater:
- Connect an external hose into the valve located at the bottom of the heater.
- Place said hose near a drain, sink, or toilet to prevent flooding.
- Turn the water heater’s power off.
- Turn the cold water valve off.
- Allow the heater to cool for about one to two hours.
- Open the drain flow knob and let the heater’s water, mineral, and sediment flow out of the tank. Leave it for about five minutes until it’s completely empty.
- Once the tank is fully drained, turn the drain valve off, and turn the cold and hot water back on.
To prevent sediment buildup in the future, we recommend cleaning the heater at least once every year, especially if the heater is an older model.
If the heater is still within its warranty period, it’s worth contacting the manufacturers so they send you a replacement or send a licensed plumber to help you flush and clean the tank.
2. Screeching or Screaming
When a water heater screeches or screams, this usually indicates restricted water flow. The heater’s safety valve, inlet valve, outlet valve, or even its water lines might be partially closed or blocked.
If this happens, check the heater’s valves and water lines and make sure everything is open.
Sizzling sounds often indicate a leak within the tank. When water drips into the burner, sizzling occurs; similar to what you’d hear when you pour water into a hot pot.
Check the surrounding area of the tank for any obvious signs of water leakage. Once you do, you can either seal the leak yourself or call a plumber to do it for you.
Act fast; the longer you leave the water heater in this state, the faster it deteriorates. Moreover, no one wants to waste water!
Water tanks that constantly leak may also indicate that it requires immediate replacement.
4. Knocking or Hammering
Knocking sounds, also known as water hammers, are directly related to the pipe’s internal heating. It usually happens when the heater’s pipes bang against the wall’s interior when the tank is turned off abruptly.
While this isn’t dangerous to your water heater, it’ll likely cause secondary wall damage if not corrected. It might also potentially ruin the pipes if left alone for too long. The easiest solution here is to simply install a water hammer arrestor between the water heater and the pipe.
A water hammer arrestor, also known as the pressure-reducing valve, is designed to protect the heater’s plumbing, tank, and pipes by absorbing the shock created by water hammers.
Ticking noises are caused by water pressure change. Water heaters usually have inlet and outlet nipples with heat traps. This is designed to improve and increase efficiency as the nipples are what directly connect the plumbing to the water heater.
Said heat traps are what often cause ticking noises. Search for the noise’s source and tighten any loose straps.
If this doesn’t work, and the noise becomes too uncontrollable and loud, you might want to replace the nipples with a non-heat trap or install spacers that’ll prevent the pipes from moving.
The nipples are located on top or under the water heater where the water plumbing, both incoming and outgoing, connects.
You can also try reducing the water’s temperature to prevent pipe expansion, and eliminate the annoying ticking sounds.
If your water heater is creating a humming noise, this may indicate that there’s a loose heating element somewhere in the tank.
When this happens, all you’ll need to do is to tighten the element a little and keep an ear out for several days. If the humming starts again, you might want to replace the element.
Water Heater Care Tips and Maintenance
A house rarely goes without a water heater. As such, proper care and maintenance must be carried out to keep it in optimal condition.
The following are some of the most important tips for taking care of your water heater!
- Drain the water tank a few times per year to remove sediment and debris build-up.
- Test the temperature-pressure relief valve on a yearly basis. You can do so by discharging the valve two to three times.
- Keep an eye out for water leakage, no matter how small. Find the source and call a plumber to help stop the leak.
- Adjust the thermostat to about 120 degrees to extend the tank’s longevity.
- Make sure to examine the heater’s sacrificial anode rod every two to three years. If the rod is less than half an inch thick or coated with a thin layer of calcium, it’s time to replace it.
Water heaters normally don’t make any loud noises. If your heater starts popping, sizzling, screeching, or humming abnormally, we encourage you to do some basic maintenance to keep your mind at ease and prevent any expensive replacements in the future.