What is a Safety Tray & Leak-Protection Device — and Why Have We Quoted It?
When a hot water system is installed indoors or in a roof space, Australian Standards require a way to catch and stop leaks before they damage your home. Here's what that means and the devices we use.
Why It's Required
When installing hot water systems indoors — especially in areas without a floor drain — a steel safety drip tray must be placed beneath the tank to capture any leaks. That tray should be drained by a 25 mm safe waste to an approved disposal point. Where a drain isn't practical, an approved automatic leak-protection / shut-off valve becomes mandatory instead.
These requirements come straight from AS/NZS 3500.4 (Clause 5.4 – Protection Against Damage From Leaking Water). It's not an optional extra — it's what makes your installation legal and protects your property from flood damage.
The Leak-Protection Devices We Use
Mildred Automatic Shut-Off Valve
A sensor sits in the safety tray and instantly shuts off the water supply the moment a leak is detected.
- Detects water in the tray & cuts supply
- Battery operated (4× AAA/AA), with a low-battery alarm
- Annual battery replacement
- Complies with AS/NZS 3500.4:2018 & WMTS-476:2016
AVG eFlow Stop Valve
A motorised stop valve fitted to the cold-water inlet that closes automatically when its sensor detects a leak — protecting the system upstream of the expansion control valve.
- Automatic motorised shut-off on leak detection
- Fitted adjacent to the cold-water inlet
- Reliable mains-pressure protection
- Meets Australian plumbing standards
Thompson Leak-Detection Valve
A leak-detection valve that monitors the safety tray and isolates the water supply the instant moisture is sensed, preventing overflow and water damage.
- Continuous tray leak monitoring
- Automatic supply isolation on detection
- Ideal where a safe-waste drain isn't possible
- Compliant leak-protection solution
Why We've Included It on Your Quote
Your system is being installed in a location that, under AS/NZS 3500.4, requires either a safe-waste-drained tray or an approved leak-protection device. Including the Mildred, AVG eFlow or Thompson valve keeps your installation fully compliant and — more importantly — actively protects your home from costly water damage if the tank or fittings ever leak.
The Standard, In Plain English
5.4.1 Concealed Water Storage Tanks
Water heaters installed in roof spaces, cupboards or otherwise concealed must sit on a safe tray drained by a safe waste. Alternatively, mains-pressure heaters may be installed on a safe tray without a safe waste, provided a leak-protection device is fitted adjacent to the cold-water inlet and upstream of any expansion control valve.
5.4.2 Unconcealed Water Storage Tanks
Tanks installed on a waterproof, drained floor don't require a safe tray. A mains-pressure heater fitted with a leak-protection device doesn't require a safe waste. All other indoor tanks must have a compliant safe tray and safe waste.
NOTE: Free-outlet storage heaters not exceeding 13.5 L, and instantaneous water heaters, do not require safe trays.
Experience and Expertise You Can Trust
When it comes to the safety of your hot water system, you want to make sure you’re working with a team that prioritizes your peace of mind. With years of experience in the industry, our skilled technicians understand the importance of adhering to Australian Standards to safeguard your property and ensure dependable water service. Don’t leave your safety to chance; choose a trusted specialist!