Hot Water Compliance for WA Rental Properties: Landlord Requirements

From what we see across Perth, most landlords only think about hot water compliance when a system actually breaks.

This reactive approach often leads to expensive emergency call-outs and potential legal exposure.

We founded Hot Water System Perth in 2021 to address exactly this gap between basic repairs and true long-term safety.

Property investors must understand that a working water heater isn’t necessarily a compliant one.

We are going to break down the specific WA regulations you need to follow and the practical costs involved in getting your property up to code.

Legal Requirements Overview

Residential Tenancies Act 1987 (WA)

We find that many property owners overlook the specific wording in the Residential Tenancies Act 1987 (WA).

Landlords must provide a property that is reasonably secure and habitable.

We know that under this Act, a failure to provide safe hot water is considered a breach of the lessor’s obligation to maintain the premises.

This obligation includes:

• Providing functioning hot water facilities.
• Ensuring all plumbing meets current health standards.
• Addressing urgent repairs (which includes hot water failures) within 24 to 48 hours.

Tenants can apply to the Magistrates Court for orders if these repairs are not carried out.

Plumbing Code of Australia (PCA)

We follow the Plumbing Code of Australia strictly during every inspection.

This code mandates the specific temperatures for water storage and delivery to prevent bacterial growth and physical injury.

We use these technical standards to determine if a system is legally passable or if it requires immediate intervention.

AS/NZS 3500.4 (Australian Plumbing Standard)

Australian Standard AS/NZS 3500.4 is the technical bible for hot water installations.

It outlines two critical, opposing temperature rules that every landlord must balance:

1. Storage Rule: Water must be stored at a minimum of 60°C to kill bacteria.
2. Delivery Rule: Water must be delivered to bathrooms at a maximum of 50°C to prevent burns.

We often see older DIY installations that violate one of these rules while trying to meet the other.

Temperature Requirements Explained

Storage Temperature: 60°C Minimum

We frequently explain to clients why they cannot simply turn down the thermostat to save electricity.

Storage tanks must maintain water at 60°C or higher to inhibit the growth of Legionella bacteria.

We know from industry data that Legionella thrives in warm water between 20°C and 45°C.

If a landlord allows the storage temperature to drop into this “danger zone,” they risk exposing tenants to Legionnaires’ disease.

This severe form of pneumonia can be fatal and results in massive liability claims against property owners.

Delivery Temperature: 50°C Maximum

We prioritize the installation of tempering valves because the risk of scalding drops significantly at 50°C.

Water delivered to personal hygiene areas (showers, basins, baths) must not exceed this limit.

We use the following data from the Victorian Building Authority to illustrate why this 50°C limit is non-negotiable for tenant safety.

Scald Time vs. Water Temperature:

Temperature	Time to Third-Degree Burn (Adult)	Time to Third-Degree Burn (Child)
60°C	1 second	0.5 seconds
55°C	10 seconds	7 seconds
50°C	5 minutes	5 minutes

You can see that at 60°C, a tenant has almost no reaction time before a serious injury occurs.

We install systems that grant that critical five-minute buffer, which is vital for elderly tenants and young children.

Where Tempering is Required

WA regulations are specific about where this temperature control must be applied.

We must ensure 50°C delivery at:

• Showers and bathtubs.
• Bathroom hand basins.
• Bidets and other personal hygiene outlets.

Kitchen sinks and laundry troughs are generally permitted to receive water at 60°C to aid in cleaning grease and washing clothes.

Tempering Valve Requirements

What is a Tempering Valve?

We consider the tempering valve the most critical safety component in any modern hot water setup.

It is a 3-way mixing valve that blends hot water from the cylinder with cold mains water.

We verify that these valves engage a “fail-safe” mechanism during our inspections.

This feature automatically shuts off the hot water flow if the cold water supply fails, preventing pure scalding water from reaching the tap.

Installation Requirements

We only allow licensed plumbers to handle these installations due to the precision required.

The regulations dictate that valves must be:

• Fitted by a licensed practitioner.
• Positioned to allow easy access for future maintenance.
• Protected by a non-return valve to prevent backflow.
• Flushed thoroughly to remove debris during installation.

Compliance Timeline for Rental Properties

We often clarify for landlords that retrospective laws apply at specific “trigger points.”

You are legally required to ensure a tempering valve is installed when:

• System Replacement: The existing hot water unit is replaced with a new one.
• Change of Layout: Bathroom renovations involve moving pipes.
• New Tenancy: While not always strictly retroactive for existing unchanging tenancies in older homes, we strongly advise installing one before a new lease begins to meet the “safe and habitable” standard of the RTA.

Properties built after roughly 1993 should already have these valves, but we find many have failed or were removed.

What Landlords Must Do

Before New Tenancy

We recommend a specific checklist to avoid disputes later.

1. Verify Valve Presence: Locate the tempering valve (usually a colored cap near the tank).
2. Test the Temperature: Use a thermometer at the nearest bathroom tap to ensure it reads max 50°C.
3. Check the Date: Look for the manufacture date on the tank; systems older than 10-12 years are ticking clocks in Perth’s water conditions.

At System Replacement

We handle the full compliance upgrade when a tank fails.

Replacing a water heater “like-for-like” without adding a tempering valve is illegal if the property lacks one.

We must issue a Compliance Certificate (Notice of Completion) to the Plumbers Licensing Board within 5 working days of the job.

This certificate is your proof of compliance if an insurance claim ever arises.

Ongoing Maintenance

We see many landlords neglect the system until a failure occurs, but preventative maintenance saves money.

Annual Checks (Property Manager/Landlord):

• Pop the pressure relief valve lever (if safe to access) to ensure it’s not seized.
• Check for water pooling around the base.
• Listen for boiling or sizzling noises (a sign of sediment buildup).

5-Year Professional Service:

• Replace the tempering valve (manufacturers recommend replacement every 5 years).
• Replace the sacrificial anode (critical in WA’s hard water).
• Check the thermostat calibration.

Common Compliance Issues

Issue 1: No Tempering Valve Installed

Risk Level: High

We still encounter older rental properties delivering 65°C+ water directly to the shower.

This creates an immediate liability for the landlord if a tenant slips or faints in the shower and cannot move away from the stream.

Action: Retrofit a tempering valve immediately.

Issue 2: Tempering Valve Failure

Risk Level: Medium

We find that valves often get clogged with debris or scale, especially in areas with high mineral content.

A failed valve may deliver lukewarm water or fail to restrict hot water at all.

Action: Replace valves that are over 5 years old.

Issue 3: Thermostat Turning Down

Risk Level: Medium

Some owners manually lower the tank temperature to 50°C to avoid buying a valve.

We warn against this because it turns the tank into a breeding ground for bacteria.

Action: Set tank to 65°C and use a valve to reduce delivery to 50°C.

Issue 4: Expired Anodes

Risk Level: Financial Risk

We consistently see tanks rust out prematurely because the sacrificial anode wasn’t replaced.

Perth water is aggressive; an anode that lasts 7 years in Melbourne might only last 4 years here.

Action: Schedule an anode check every 3-4 years.

Insurance Implications

Public Liability

We have seen cases where insurance claims were complicated by a lack of maintenance records.

If a tenant suffers a third-degree burn and sues for negligence, the court will ask for proof that the system was compliant.

We provide documented invoices and certificates that serve as this proof.

Landlord Insurance Exclusions

Most Product Disclosure Statements (PDS) for landlord insurance contain a clause regarding “legal compliance.”

The insurer may deny a claim for water damage (e.g., a burst tank) if they discover the tank was installed illegally or by an unlicensed person.

We ensure every job generates the necessary government paperwork to protect your coverage.

Property Manager Responsibilities

Duty of Care

We partner with property managers who understand that “setting and forgetting” is not an option.

Property managers must:

• Report any hot water complaints to the landlord immediately.
• Avoid approving “handyman” repairs for plumbing works.
• Keep a digital paper trail of all refusal of advice by landlords.

Documentation

We assist agencies by automating the compliance certification process.

Audits by the Department of Mines, Industry Regulation and Safety (DMIRS) can request maintenance logs.

Records you must keep include:

• Notices of Completion from plumbers.
• Invoices detailing the scope of works.
• Tenant correspondence regarding water temperature.

Cost of Compliance (2025/2026 Estimates)

We believe in transparency regarding current trade pricing in Western Australia.

Prices have risen due to material costs, but compliance remains cheaper than a lawsuit.

Estimated Costs for WA Landlords:

Service	Estimated Cost (ex GST)	What’s Included
Tempering Valve Retrofit	$380 - $650	Valve, copper pipe modifications, labor, testing.
Standard Service Call	$180 - $280	Diagnostic, minor adjustments, temperature check.
Anode Replacement	$250 - $350	Part and labor (extends tank life by years).
Compliance Inspection	$180 - $300	Full report on temperature and valve status.

Note: Access difficulties or older non-standard piping can influence these figures.

Getting Your Property Compliant

We specialize in bringing non-compliant rentals up to code efficiently.

Our team focuses on:

1. Audit & Assessment: We test temperatures and check valve dates.
2. Valve Installation: We install WaterMark certified tempering valves.
3. Paperwork: We lodge the required Notice of Completion with the state regulator.

We act as a safeguard for your investment, ensuring you stay on the right side of the Residential Tenancies Act.

Summary

Hot water compliance in WA is binary: your property is either safe and legal, or it is a liability.

We urge you to remember the four pillars of compliance:

• Storage: Keep it above 60°C.
• Delivery: Cap it at 50°C.
• Hardware: Install a functioning tempering valve.
• Maintenance: Service the system every 5 years.

Taking action now prevents scalding injuries and protects your insurance validity.

Contact us today to schedule a comprehensive hot water compliance audit for your rental portfolio.