How Does a Shower Work?

So, how does a shower work? Well, it’s pretty easy! You turn on the tap, get the temperature of the water right and adjust the shower head to get the water flow pressure equally right. Then you stand under warm water for however long you need while thinking about life’s biggest problems.

We hate to say it, but there’s a little more to shower plumbing than that. Behind the scenes of your shower system, there’s a world of fixtures, fittings and drainage.

We’re not planning to provide a boring rundown of the mechanics, no. The only time we’ll mention technical terms like tub spout and diverter valve is right here, right now. That’s it. We want to give easy explanations so you can be better prepared the next time you need to call a plumber.

What System Parts are Behind the Wall?

We’re all very familiar with the parts of the shower that we see and touch every day, such as shower heads and the shower drain. But how about those parts that we don’t see, those that are concealed but keep things chugging along?

Starting with the basics, typically you’ll find these components behind a shower wall:

• Pressure balancing valve or thermostatic mixing valve
• Cold water supply
• Hot water supply
• Shower head riser

Let’s start with an easy explanation. Hot water pipes and cold pipes separately funnel water into the pressure balance valve. It is here where they combine when you turn on the taps, with the water moving up the shower head riser and out of your shower head.

The valve is where everything gets a little more technical. Inside, it keeps the hot and cold water separate until you’re ready for them to mix and turn the taps.

Understand the Different Valve Types

A pressure balance valve adjusts the mix of hot and cold water to maintain a steady temperature when there are changes in water pressure. So, if someone flushes a toilet or starts the dishwasher, it helps prevent the shower from suddenly going ice cold or scalding hot.

A thermostatic mixing valve, on the other hand, is a bit more sophisticated. It keeps your shower water at the temperature you’ve set, regardless of fluctuations in the water supply temperature or pressure.

This means even if the cold water pressure drops or the hot water temperature varies, your shower temperature stays constant. It’s great for a consistent temperature shower, but it’s generally pricier than a pressure balance valve.

As for the tempering valve, another one you may have heard of, you’ll typically find it installed on or near the hot water system. Your hot water tank stores water at a temperature of 60°C to kill off any Legionella and other bacteria.

But to reduce the risk of scalding while you’re standing on the shower floor, the tempering valve keeps the water going to your bathroom at a safe temperature of 50°C (or 45°C in hospitals, schools and nursing homes) in line with Australian Standard AS/NZS 3500.4.

What is a Power Shower?

You may have heard of the term “power shower” and thought to yourself, “I like the sound of that … I want some of that in my bathroom!” So, what is a power shower?

Power showers are predominantly a UK-centric term, but they are available in a certain form here in Australia too. It uses an integrated pump to enhance the water flow, transforming a low-pressure trickle into a robust stream.

Unlike a regular shower, which is at the mercy of the water pressure in your home, power showers ensure a consistently strong spray. It’s an ideal upgrade for an invigorating shower, though it’s worth noting that this added luxury does come with increased water and energy usage.

Here in Australia, it is possible to boost the water flow in your shower. However, under strict national regulations, you must comply with Water Efficiency Labelling and Standards (WELS) and water service rules.

What’s Up with My Shower Drain?

Shower drains are more than a hole in the ground. If you could see the whole drainage setup, you’d find a:

• A P-shaped drain trap
• Drain pipe
• Reducer or reducing coupling
• Drain riser pipe
• Main vent stack

The drain trap is P-shaped for optimum flow and hygiene. It catches all the bits of soap, hair and whatever else flows down the tub or drain hole. The P shape allows water to pool at the bottom, forming a watertight seal that prevents unwanted sewer smells from sneaking into the bathroom.

Staying on nasty odours, the main vent stack also helps keep your bathroom smelling fresh. The vent stack runs out of the piping, through the wall and eventually pops out of the roof.

Allowing air to flow through means the water flows more freely and no gases build up.

How Does the Shower Head Work?

Your shower head is where the real variety comes in. Much of it comes down to the look and functionality, but there is an increasing amount of low-flow, environmentally friendly shower heads available.

Inside the shower head, flow controllers limit the flow of water and pressure according to its WELS-rated level. Under the national WELS scheme, most new builds use 3-star heads capped at ≤9 L/min; 4-star models are typically ≤7.5 L/min.

Now, when it comes to the actual shower head, that’s up to you. Spray types can vary, and include:

• Aerating: water mixes with air, creating wider coverage with a more mist-like spray
• Laminar flow: water is separated into individual streams for a direct approach

The wall-mounted fixed shower head is your traditional style. There is also the handheld shower head that provides versatility and convenience. Rainfall showers give you a tropical resort feel, while something like a filtered shower head ensures you have the cleanest water possible.

Your Shower Plumbing Experts

Are you looking for shower drain pipe repairs, a new mixer shower head installation, or any other bathroom plumbing services? Contact the customer service team at Metropolitan Plumbing, and we’ll dispatch a licensed and experienced plumber to your location, backed by our same-day service promise.

Please note: Thanks for reading our blog “How Does a Shower Work?”. This information is provided for advice purposes only. Regulations differ from state to state, so please consult your local authorities or an industry professional before proceeding with any work. See our Terms & Conditions here.

Frequently Asked Questions About Showers

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