External Hot Water Cylinders Wellington
External hot water cylinders are good for households which require extra space. A hot water cylinder occupies a lot of space inside the house, but with the external hot water cylinders, you can use that space efficiently. There are water tanks designed especially for external use and the casing is waterproof.
Dux, Parex, and Rheem manufacture external hot water heaters. They are available in a wide range of sizes. The most popular models are around 180 litres for standard domestic use.
External Heat Pump Water Cylinders
Heat pump water heaters can often be installed both inside and outside. Heat pump water heaters are often installed in the garage and have ducting inside the roof apex. It captures the waste heat generated in the ceiling. This improves its heating efficiency. They cannot be installed in cupboards inside without the ducting.
Parex manufactures a heat pump tank called EcoSpring. It comes in 190 and 300-litre models. It is one of the most efficient water heaters in the market including gas tank. It uses about 1kW of electricity for 3 kW input into the water. With electricity at 23 cents per kW, the real cost is about a 1/3 of that, which is about the cost of gas.
Vulcan Free Loader Replacement model
Rheem produces an external gas tank called a Stellar model which is gas powered. It replaces the old Vulcan Freeloader gas water heaters.