Different types of Gas Water Heaters

All instant water heating products are rated Litres per Minute (l/min), this refers to the flow rate that the unit will heat the incoming water temperature up by 25 deg.

In order to heat the the water to say 45 deg, the flow through the unit will be about half of the rated number i.e. to get 45 deg from a 16lt/min unit, the water will flow about 8-10lt/min.

You get 2 types of gas water heaters. The first is the basic type that doesn’t require any electrical connection and is available in various sizes, 6, 8, 10, 12, 14, 16 & 18lt/min.

These units have a battery ignition system. They do require certain water pressure to work (250kPa Minimum).
The second type is a forced exhaust system. This is an electronically controlled system that requires 220v to work. The output temperature can be set with or without a digital control panel that is installed inside the house.

These units have a fan that forces air though the burner resulting in higher temperatures from smaller burners. These types of units are used for larger consumptions of hot water and are available in 16, 20, 24, 26, & 32lt/min