Why Is My Water Heater Making a Sizzling Sound?

Sediment is present in all water sources in the UK, whether you’re on a well or the municipal water supply. It includes fine grains of sand but is mostly comprised of minerals like lime, calcium, and magnesium. As you use the water heater, sediment in the water settles out and begins coating the inside of the water heater from the bottom up.

In a situation where the water heater is creating a sizzling sound, the issue is likely that water is becoming trapped in the sediment on the bottom of the cylinder. Here, it boils, turns to steam, and sizzles while trapped between the bottom of the cylinder and the sediment layer.

Finally, some situations involving a sizzling sound relate more to valve issues than anything else. The most common culprit is the temperature and pressure relief valve – listen closely near the valve while the unit is operating. If the sizzling sound is coming from here, turn off the unit and call a qualified repair professional.

In addition to sizzling sounds, water heaters can make many other noises as they age. We’ll run through some of the most common below.

Popping – If you’re hearing a popping noise from your unvented cylinder, then chances are good it’s related to sediment build-up at the bottom of the tank. As sediment increases, water becomes trapped, boils, and then bubbles up through the layers, creating a popping sound. The only way to stop this is to drain and flush the cylinder, removing the build-up in the process.

Screeching – A screeching sound from your unvented cylinder is sometimes an indication of restricted water flow into the unit. Check the inlet control valve and make sure that it is fully open and not partially closed. Thankfully, this is a relatively simple fix! However, if you check the valve and it’s fully open, but the screeching sound continues, call for professional help.

Hissing – Many different things can cause hissing sounds with your water heater. One of those is condensation running down the outside of the cylinder, and then coming into contact with hot surfaces, such as the area around the burner in a gas-fired water heater. Condensation is sometimes normal when you use a large quantity of heated water very quickly and the unit is refilled with cold water from the mains.

If you’re experiencing any of these issues, get in touch with EasyFlow today. One of our trained specialists will help get your system up and running again.

EasyFlow can send an engineer to you if you’re located in Greater Manchester, Warrington, Liverpool and Chester.