Why gas geysers?

To avoid warm water growing stuff in it, it needs to be kept at a minimum temperature of 55 degrees, which is why geysers use so much energy. A gas geyser does away with the need for a storage tank as water is heated instantaneously when it is required. However this method requires a large amount of gas and is more suited to area’s that have piped gas (like Europe). Piped gas tends to be more cost effective than bottled gas.  If bottles are used, 45Kg bottles are the best option.

What to consider when choosing a gas geyser

Gas geysers are generally installed externally and should be considered in planning stages to avoid them being an eyesore. Certain units require an exhaust, which has a fairly ugly flue with a Chinese type top hat.

Gas geysers have different flow rates, so get advice to ensure that you select a geyser with an adequate flow rate per second for the required application.

Consider what type of igniter the gas geyser uses. Gas geysers generally make use of electrical igniters, but not all have a backup system, for when the power is out.

Gas geysers may also require a certain amount of water pressure to function optimally, keep this in mind if you are in an area where the water pressure is low. It may also be a good idea to check what water pressure your taps require especially if you are using ‘water saving’ technology taps.


In applications where large amounts of hot water are required (bathrooms), and piped gas is not valuable gas may be an expensive alternative to electrical heating. However, gas presents a great option for kitchens where small amounts of hot water tend to be used at intermittent intervals. If using solar geysers for the house hold water it’s often a great idea to install a gas geyser in the kitchen to avoid diluting the solar water store.

Guest suites are also well served with gas and offer redundancy when combined with solar systems.


The advantage with a gas system is that you are not using heaps of power and resources to heat a tank of water for 24 hours which is used for a few minutes of the day. It may however prove expensive as gas is still a resource.

This architect’s conclusion is that gas is great where small amounts of hot water are required intermittently, as part of a water heating system, or where gas is inexpensive!

This post is a part of the ‘in hot water ‘series and should not be read in isolation.

 Please see my conclusion on this issue of water heating.