July 29, 2022

Popping noisy hot water unit

Storage Hot water unit maintenance and replacement

Hi guys,

Welcome to Prompt Plumbing and Electrical. We get inquirys from a clients that the hot water system is making funny noises. The system in question is generally a Rheem stellar.

When you hear that noise?  It’s like a, a sort of rumbling, popping noise, in the industry we call it kettling. So what that means is the hot water system is due a major service. This can start happening as early as 3 years into the Hot water unit life. The manufacturers recommends that a licensed plumber carries out a major service. A major hot water service should be done after about four to five years. One of the major contributors to this problem is water quality. A major service on a Rheem stella entails a tank flush and replacement of 2 anodised rods.

Inside the Rheem stella hot water system, there are 2 sacrificial anodes (rods), which are basically 2 long magnesium rod’s. The magnesium rod are positions between the flue in the centre of the tank and the outer layer. What the rods do is sacrifices themselves to the impurities in water like corrosion. Thus prolonging the life of the hot water unit.

The hot water cylinder is manufactured out of steel and lined with enamel. This enamel is designed to fall away over time.

After a period of time your hot water unit will collect debris, enamel and anode debris at the bottom of the tank. This accumulation of debris reduce the efficiency of your hot water unit as well as being a noisy nuisance.

The debris can and do with use of your hot water get sucked into your taps and valves causing obstructions. General symptom is low water flow.

So it’s, it’s still got some in the center, but the very top of it is broken down to absolute nothing. So that’s basically just a, like a steel supporting rod to hold it all together. Um, so yeah, but basically what happens is the UN unloaded rod breaks down. Now, all of that, I know all the, I know sediment, uh, has to go somewhere. So what happens is it actually sits on the very bottom of the tank. Okay. So when the hot water system’s heating up, like this one is now, you can see it’s steaming, okay. All that sediment is set on the bottom of the tank. And it’s just basically going around in circles and circulating, like with a, a kettle, when you’ve got lime scale, build up, you turn the Kele on, it makes a bit of noise. Well, it’s exactly the same thing.

In Perth we recommend a tank flush every 3 years as the large debris become hard to flush out. Don’t hesitate to call us for all your plumbing services 9249 9638

Other symptoms you may experience is gassing – this is caused by the anode not being suitable for the water.

Below is a video of us cutting open the tank


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