What to consider before buying a gas geyser?
Gas geysers are a confusing topic and this is understandable. They are also known as gas water heaters and unlike traditional geysers they do not store water internally. These geysers heat water on demand, essentially only heating water when your hot water tap is turned on.
How does a gas geyser work?
A gas geyser can be confusing to understand however referring to it as a Gas Water Heater is more suitable as this is exactly what it does – it heats water using a gas flame. The water is pumped through a radiator which is heated up using gas. There is no storage tank inside the geyser, so water is only heated when it is flowing through the unit and a certain flow rate is required to trigger the gas ignition.
Understanding flow rate
Gas geysers typically operate within a flowrate range. For example, a 12L gas geyser may operate between 6L/m and 12L/m. Flow rate is quite simply the volume of water moved through a pipe per minute. Using our example of a 12L gas geyser, this gas geyser can heat up to 12L of water every minute. On the flip side, it is only capable of heating a minimum of 6L a minute. Hence, the range of 6 – 12L.
Flow rate should not be mistaken with pressure. Flow rate is determined by 2 things: Your water pressure and the diameter of the pipe. For example, if you have a 1cm diameter pipe and a 10cm diameter pipe, both with 6bar pressure. The 10cm diameter pipe will obviously have a higher flow rate.
What size geyser should I get?
This depends entirely on what you are using it for, the layout of your house and how many hot water taps you expect to have on at any given time. A bath will require a geyser of 12 – 16L and a shower about 6L/min. Here is a helpful graphic below that will help you establish what you may need to consider: