Gas Water Heater Selection Guide

Gas Types

Natural Gas (N.G.) is primarily made up of the hydrocarbon Methane. N.G. is the most common gaseous fuel in Australia and is one of our largest exports.  Underground pipelines supply Brisbane properties with natural gas via a metered connection. Notable Brisbane areas which we regularly service for Natural Gas Appliances include Indooroopilly 4068, Toowong 4066, Paddington 4064, Ashgrove 4060, Ascot 4007, Bulimba 4171 and Balmoral 4171. Natural Gas is the most cost-effective fuel type  in medium to high use applications (i.e. properties with 2 or more people). For more information on gas availability, please refer to Brisbane’s Natural Gas availability map

L.P.G. (commonly referred to as propane), is supplied via storage cylinders. Depending on the application, these cylinders are either “swap-and-go” or filled in situ by the gas supplier. Throughout Brisbane, L.P.G. fuels cooking appliances, gas cook-tops and hot water heaters.  Low volume users and properties limited to 1-2 people may find L.P.G. gas cheaper than Natural Gas, as it does not incur metering costs.

Available Water and Gas Supply

The quality of water and gas services available at your property may impact your options as a consumer. If you have a Natural Gas connection in Brisbane, the supply can either be Low (1.2kpa) Medium (2.75kpa) or High Pressure (2.75+kpa).  It is important to consider the available pressures when selecting a gas water heater to ensure the water heater can work to its full capacity. In some instances it is possible to request a gas pressure upgrade if the mains supply pressure exceeds the meter outlet pressure.

Service Requirements and Pipe Sizing

A Continuous Flow gas water heater, such as the Rheem Metro, Dux EN and Rinnai Infinity range, requires the following:

– A power source (such as a weatherproof GPO).
– 20mm gas service which can deliver up to 150Mj/h.
– A water service with a suitable flow rate (old galvanised pipes may cause flow issues).
– Flow restrictors may also require removal to achieve adequate flow rates.
– As these systems have inbuilt temperature controllers, they do not require tempering valves.

A Storage gas water heater, such as the Rheem Stellar, Aquamax 270SS and Dux Prodigy range, require the following:

– Non-return isolation valve, pressure and temperature relief valve (PTR), expansion control valve (ECV) and tempering valve.
– A drain line which complies with the plumbing and drainage code.
– A prefabricated base.
– 15mm (1/2”) gas line or greater.

Efficiency

The AGA (Australian Gas Association) uses a star rating system to label gas hot water units.

Storage tanks range from 3 – 5 star efficiency.

Continuous Flow gas water heaters range from 5 – 6.7 star energy efficient.

Condensing Continuous Flow gas water heaters range upwards of 6.5 energy efficient.

Construction Of Tank

Vitreous Enamel (VE) tanks are a “tried and tested” traditional construction. Chances are, your current hot water unit is VE. This construction is an enamel coated steel which uses a sacrificial anode to help prolong the life of the tank. Rheem and Dux are two reliable manufacturers of Vitreous Enamel gas hot water heaters. Warranty periods for VE tanks range from 5-12 years.

Stainless Steel gas hot water heaters are a relatively new introduction into the Australian Market. This construction is a premium product which offers an increased lifespan and warranty period. Stainless Steel tanks do not have an anode and instead rely on a protective coating. SS tanks such as the Rheem Stellar range, carry an impressive warranty of up to 12 years however do not carry a manufactures warranty for areas with poor water quality. For more information, please refer to Rheem’s Suitability map.