Glossary of Terms
Do you find some terms for hot water systems confusing? Please let us try to explain them for you;
Storage Hot Water Tanks
Storage hot water tank is a water tank that is used for storing hot water. The water is heated up and stored waiting to be drawn off when the tap is opened. Once all the “stored” water is used, the water is the tank must be heated up again. They are classified by their storage capacity generally ranging from 50 Litre to 400 Litre. They are available in either a single element or a double (twin) element.
Continuous Flow Water
Continuous flow heaters are also known as an instantaneous heater. These heaters do not store hot water inside them but actually heat the water when the hot water tap is turned on. They are classified by the amount of water they can heat per minute e.g. 27 L per minute
Tempering Valve
Tempering valves are a requirement under AS/NZS3500 (Australian Plumbing Standard) and must be fitted to any tank replacement. These valve mixes hot water coming out of the tank with cold water to provide hot water at your taps at no more than 50 Degrees Celsius.
Safety Tray And Automatic Shut Off Device
As per AS/NZS 3500, all water heaters that are installed indoors and are in concealed locations i.e. cupboards or in non wet area (areas without a drain in the floor) require a safety drip tray and either a drain off the tray or an approved automatic shut off valve ( we install the Mildred valves, this device has a sensor that sits in the tray of the hot water tank and if it detects water in the tray automatically shuts off the water flow to the hot water system. to protect yours and other peoples property from damage)
Solar Hot Water
Solar hot water heaters uses the heat from the sun to heat the hot water. There are two main types, Lowline – where the tank is on the ground and the panels are on the roof and Highline – where all components are on the roofs. These heaters usually also have either a gas or electric back up capacity for when the solar gain will not heat the water enough.
Duo Valve
The duo valve was actually two separate valves. The first one was the stop tap, this is a tap that you turn off to stop water flowing into the heater. The second one is a non return valve that stops the hot water in the tank coming back out of the hot water tank and down the cold pipe. These two valves have been turned into one valve that does two actions, hence the name duo. It allows you to quickly shut off the hot water supply only in the case of an emergency or when work is required to be done on the hot water plumbing .
What is a storage hot water system?
A storage hot water system heats and stores water in a tank until it’s needed. These systems are common in Sydney homes and are available in electric, gas, and solar models. Tank size determines how long hot water lasts before reheating is required.
What is a continuous flow / instant hot water system?
A continuous flow system heats water only when a tap is turned on, meaning you won’t run out of hot water. These systems are compact, energy-efficient, and popular for households with higher hot water demand
What does a tempering valve do?
A tempering valve mixes hot and cold water to deliver water at a safe temperature, usually capped at 50°C. Tempering valves are required under Australian plumbing standards to reduce the risk of scalding.
Why is water leaking from my hot water system relief valve?
Water discharge from the pressure relief valve usually means the system is relieving excess pressure or temperature. Occasional dripping can be normal, but constant leaking may indicate a faulty valve or pressure issue that should be checked by a licensed plumber.