What is a gas hot water system?
Gas hot water systems have been a common feature in Australian households for decades. Why? Because they are reliable and strong systems that maintain energy efficiency and low carbon emissions, in spite of Australia’s ever changing hot water system market. That is why Australian families have chosen gas hot water systems, and will continue to well into the future. We recommend keeping updated with our gas hot water systems review feature in order to stay informed on price and technology.
With lower up-front installation costs, lower maintenance costs and, where natural gas is available, lower energy costs – gas hot water is the most affordable option in Australia.
If you don’t have access to natural gas in your area, you will need to become connected to the mains gas line or a use a bottled gas in order to access LPG. However, LPG is a more expensive option to run than natural gas.
There are two main types of gas powered hot water systems for you to consider:
- Storage hot water systems: heat and store hot water inside an insulated tank for use when needed
- Continuous flow systems (or Instantaneous gas hot water systems): heat water on demand do not use a storage tank
Advantages and Disadvantages of Gas Hot Water Systems
- Produce less greenhouse emissions than electric hot water systems
- Continuous Flow systems can provide “unlimited” hot water
- Lower upfront costs than solar or heat pump systems
- Most sustainable and energy efficient option outside of solar power
- Lower installation costs when no gas line upgrade is required
- Reliable and dependable
- Relatively simple operation
- Can be turned off when not in use
- Gas is a more cost-effective option than electrical
- Large tank size for storage systems, can take up space
- Storage units can experience some heat loss
- May need to upgrade gas line for use
- Can result in water loss in some continuous flow systems
- Access to “unlimited” hot water may result in higher energy costs
- May be more expensive option if LPG is the only gas available
Storage unit systems are the most widely-used variety of gas systems. They are an effective choice in any climate and can provide hot water throughout the day and night through their continuous heating system. Storage unit systems work the best for those in larger households, or in households with higher hot water use as a large amount of almost “unlimited” hot water is available throughout the day.
Storage unit systems are distinctive, as the hot water is stored in a large cylindrical tank, they are one of the most common hot water systems in use throughout Australia, and are well-known for being reliable, and low-maintenance, making them a popular choice of hot water system for thousands of Australians.
Enamelled steel is the most common material used to make storage units, however stainless steel is also an option. Stainless steel is usually a more expensive option, however it does not require eh same maintenance that the enamelled variety does. Enamelled tanks rely on the sacrificial anode, usually made of magnesium, that protects the inside of the s=tan from corrosion. These usually needs to be checked or served every five years, however is the only basic maintenance needed for the storage tank variety of hot water system.
How does it work?
Storage hot water systems operate mainly by the main tank being heated by a gas burner located beneath the tank. The burner supplies a continuously burning flame that creates the warmth for the entire tank. A hot flue pipe is also connected to the burner, and it contributes to the flow of heat through the water. The water is heated from the bottom of the tank and rises. When hot water from the bottom of the tank is used, cold water is pumped into the bottom of the tank, this creates a continuous motion of rising warmth throughout the tank to sustain hot water throughout the day and night.Most storage systems run off a gauge that stabilises the temperature of the water in the tank. Storage systems needs to have their water heated to 60 degrees Celsius in order to prevent the growth of any bacteria, and to ensure a nice warm temperature for your water at all times.
It is not only a health concern that the storage systems be heated at 60 degrees, but higher temperatures tend to waste more energy. So for the interest of the environment and your back pocket, keeping the system at around 60 degrees will save you more.
One of the disadvantages of storage heaters is that they can lose heat through the walls of the tank, this is called standing heat loss. To combat this, the tanks needs to make up for the loss of heat by burning extra gas in order to keep the water at the desired temperature. It is because of this system that the storage tank are not the most sustainable option when it comes to instant gas hot water systems, however they still remain a lot more sustainable and energy efficient than the electric systems. All tanks are designed to have an insulated lining to reduce heat loss. There are more and more tanks on the market that have thicker insulation to combat this issue, the thicker the insulation, the better recovery of heat you will have. These tanks are ranked by energy star ratings from about 3 – 5 stars.
- Up front purchase and installation costs lower than most hot water systems
- Strong and reliable
- Sustainable and energy efficient option
- Recommended option for those with access to natural gas
- Large tank size takes up space
- Heat loss can occur whilst in use and not
- Not as energy efficient as solar option
- Seemingly “unlimited” supply of water can result is heightened hot water use, therefore higher cost
The continuous flow, or instantaneous gas hot water systems, is the most sustainable hot water system option outside of solar powered hot water. With its reliance on the natural resource of gas, and its water conserving attributes, the continuous flow system boasts a reduced production greenhouse emissions due to the lower emission of energy it uses and the size of its system, and also conserves water as it delivers only as needed.
Continuous systems typically operate through the use of natural gas or LPG, however there are various systems that can be operated through three phase electricity.
How does it work?
The second operating system uses an electric thermostat to control the temperature of the burner flame, and works alongside fans that improve the efficiency of combustion, therefore, the speed to which the water reaches you. These styles allow the temperature of the water to be set at different temperatures for different times for plumbing requirements, or to set the temperature for a bath or shower.
- Save space as there is no huge tank to worry about
- Heats water as you need it, “unlimited” hot water for you and your family
- Most sustainable and energy efficient option for gas powered hot water systems
- Thermostats and other accessories can be connected to the system to control the temperature of water around the house
- May need to upgrade gas line to install new system
- Most units will need to be plugged into a powerpoint, so water is not available in power outage
- Higher upfront and installation cost
- Hot water delivered to a reduced pressure when more than one tap is in use