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Causes of a Whistling Water Heater

Your water heater works hard to make sure you always have access to a hot shower when you want one. However, since the water heater works quietly behind the scenes, you might forget about it for years. Then you start hearing whistling sounds coming from the water heater and become concerned.

Read on for four possible reasons why your water heater is making this noise and help deciding whether you need to call a plumber.

Why Is My Water Heater Whistling? 4 Common Causes

1. TPR Valve

As your water heater works, heat and pressure build up inside the tank. Under normal conditions, the pressure never builds to a dangerous level. In case it ever does, the temperature pressure relief (TPR) valve opens slightly to allow pressure to escape the tank. This is a safety measure that prevents your water heater from posing a threat to your home, and it’s the most likely reason your water heater is whistling.

2. Drain Valve

Near the bottom of every water heater tank is another valve. This valve exists so you can periodically drain sediment that builds up on the bottom of the tank. If the valve isn’t closed tightly, it could allow air to pass inside and cause a whistling sound.

3. Water Inlet and Outlet

On top of the tank is a cold water inlet and hot water outlet. Over time, the connections here may wear out, especially on the hot outlet side. If the whistling noise is most prominent while you’re running hot water, this is a likely source.

4. Cracked Tank

It’s also possible the tank has rusted through and formed a crack, allowing air to blow in or out and create the sound you’re hearing.

Is a Whistling Water Heater Dangerous?

Whistling noises from your water heater are a sign that a failure is imminent. The whistling sound should be considered a warning that your water heater is malfunctioning. It is a warning that requires immediate attention from a certified HVAC or plumbing professional.

Whistling from the water heater can indicate excess pressure building within the tank and problems with the TPR valve. It can also indicate cracks in the tank and a buildup of sediment within the drain valve. Each of these can cause an explosion.

It is not unheard of for enough pressure to build up to launch the hot water heater through the roof when an explosion occurs. Thus, any whistling from your hot water heater should be treated as an immediate emergency.

If your hot water heater is whistling, you should turn off the hot water heater right away. If the whistling is caused by excess pressure within the tank, this will help reduce the risk of explosion. It will also give the system time to cool off before the repair technician can arrive. For your safety, you should not attempt to make adjustments, test connections, clear drains, or other action. In fact, it is best if you and your family evacuate your home as an added precaution while you wait for the water heater repair technician.

When the repair professional arrives, they will check the connections, drain valve, TPR valve, and other components to identify the cause of the noise and the precise problem with your hot water tank. The repairs may entail replacing the TPR valve, clearing the drain valve, or replacing the tank if it is cracked or damaged beyond the point where repairs are not feasible.

Contact Arctic Air Conditioning at 732-455-9110 to schedule emergency water heater repairs and for more information about the signs your water heater poses a threat to your health and safety.

Water Heater Repair in Central Jersey

No matter the cause, a whistling water heater deserves attention. Turn off the appliance and check that all connections are tight. Also, look for any rust that could signify a crack in the tank. If everything seems in order but the water heater continues to whistle when you turn it back on, the tank is probably overheating and causing the TPR valve to open and release pressure. This could be dangerous over time, so call an experienced New Jersey plumber to take a look.

If your water heater is beyond repair, a replacement may be needed. If you need a new unit, we offer Bradford White water heaters, A.O. Smith water heaters, and Rinnai water heaters.

If your unit is making a whistling noise, contact Arctic Air Conditioning today. One of our experienced specialists will determine the problem and make recommendations for repairs or replacements!

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