Hot Water Systems: Mount Maunganui, Tauranga, Papamoa

It can be, if your household uses a lot of hot water. EECA says a heat pump uses 60 to 75 percent less electricity than a standard cylinder, and costs around $7,000 installed. For smaller households, it can take a long time to pay back the extra cost.

Check the label on your cylinder first. If it doesn't say mains pressure, other signs of low pressure are a header tank in the roof, a vent pipe through the roof, and showers that are noticeably weaker on hot than on cold.

Usually not. Most of the time it's the cylinder and valves that change, plus any shower mixers that only suit low pressure. In older homes we check the pipework first, because weak joints can leak under higher pressure.

Usually 250 to 300 litres, depending on how many showers you have and how long they are. A 180 litre cylinder is the most common size, but it suits smaller households better.

In most homes, a heat pump is cheaper to run, especially if you're paying daily gas charges or renting LPG bottles. Gas is handy because it never runs out. We'll talk you through the costs for your house.