Is a Tempering Valve Required in WA? What You Need to Know for Your Hot Water System in Perth

Is a Tempering Valve Required in WA? What You Need to Know for Your Hot Water System in Perth

If you’re planning a hot water system replacement in Perth, one important component you might hear about is the tempering valve. But what is it exactly, why is it required, and how much does it cost? Whether you’re installing a new electric, gas, or solar hot water system in Perth, it’s critical to understand the role of this small but vital device — especially if you want your installation to meet Western Australian plumbing regulations.

In this blog post, we’ll break it all down so you can be confident you’re making the right decision for your home’s hot water system.

What is a Tempering Valve?

A tempering valve is a plumbing safety device that blends hot water from your system with cold water to deliver water at a safe, regulated temperature — usually set at 50°C for domestic bathrooms.

This helps protect you and your family from the risk of scalding, especially in homes with young children or elderly occupants. In short, it ensures your hot water system delivers safe hot water to taps and showers — without being dangerously hot.

Is a Tempering Valve Required in WA?

Yes — in Western Australia, a tempering valve is legally required when installing or replacing a hot water system that supplies bathrooms. This includes all hot water system replacements in Perth unless you’re replacing a like-for-like system and the original valve is still compliant and functioning correctly.

This requirement is based on Plumbing Technical Note 2 issued by the WA Department of Mines, Industry Regulation and Safety (DMIRS), which outlines the standards for hot water installation compliance. According to these standards:

All new or replacement hot water systems that deliver water to sanitary fixtures (bath, shower, or hand basin) must include a temperature control device such as a tempering valve.

The only exceptions are:

• Systems supplying only kitchen or laundry taps (non-sanitary fixtures).
• Systems installed in aged care facilities, schools, or hospitals — which require thermostatic mixing valves (TMVs) instead of tempering valves, as they offer even more precise control.

Why Is It So Important?

In Western Australia, scalding injuries are unfortunately not uncommon, particularly in homes with outdated or unregulated water systems. Just 1 second of exposure to 70°C water can cause a third-degree burn. A tempering valve drastically reduces this risk by capping water temperature to 50°C.

Besides keeping your family safe, using a tempering valve also ensures your hot water system in Perth is compliant with AS/NZS 3500.4 and relevant WA plumbing regulations — something every licensed plumber must adhere to.

How Much Does a Tempering Valve Cost in Perth?

The cost of a tempering valve installation varies depending on your existing setup, but you can expect:

• Tempering valve supply cost: $80 to $140
• Installation cost: $100 to $250 (depending on pipework adjustments)
• Total cost: Typically between $180 and $390

If you’re getting a hot water system replacement with Ember Plumbing & Gas, we include tempering valve supply and installation in your hot water system quote — so there are no hidden surprises.

We’ll assess whether a new valve is required based on your home’s plumbing and ensure everything is up to code.

Signs Your Tempering Valve Might Need Replacing

Tempering valves generally last 5–8 years, but they can wear out over time. Here are some signs it might be time for a tempering valve replacement in Perth:

• Fluctuating hot water temperature
• Water not getting hot enough (even if the system is working fine)
• Unusual noises or vibration from the valve
• Leaking around the valve body

If you’ve noticed any of the above, it’s best to have one of Ember’s licensed Perth plumbers inspect your system.

Can I Remove My Tempering Valve?

No — not legally if your hot water system is connected to sanitary fixtures.

Removing or bypassing a tempering valve is a serious compliance breach and can result in:

• Unsafe water temperatures
• Voiding of warranties
• Non-compliance with building codes
• Liability in case of injury or inspection failure

A licensed plumber in WA is not permitted to sign off on or certify a hot water system installation that does not include a functioning tempering valve (unless exempt).

Why Choose Ember Plumbing & Gas?

At Ember Plumbing & Gas, we specialize in hot water system installation and replacement in Perth. We supply and install all major brands including Rheem, Rinnai, Bosch, and iStore, and we include all standard compliance components like tempering valves in our pricing.

When you book with Ember, you get:

• ✅ Transparent pricing (no hidden tempering valve fees)
• ✅ WA plumbing code compliance guaranteed
• ✅ Fast, same-day service available
• ✅ Free advice on which system best suits your needs
• ✅ 5-star rated service from Perth’s trusted plumbers

Need a Hot Water System Replacement in Perth?

Whether you’re upgrading to a solar, electric, instantaneous, or gas storage hot water system, Ember Plumbing & Gas is your go-to expert for safe and compliant installations.

<p”>We handle everything from:

• Tempering valve installation
• Pipework upgrades
• Removal of old units
• System advice based on your household size and usage

Contact Ember for Expert Help Today

If you’re unsure whether your system needs a tempering valve, or you want a quote for a hot water system replacement in Perth, get in touch with Ember Plumbing & Gas.