Hot Water System Plumbers in Invercargill

Hot water system costs in New Zealand vary by type. A standard electric cylinder (135 to 180 litres) costs $1,500 to $2,500 installed. A mains-pressure electric cylinder costs $2,000 to $3,500. A gas continuous-flow (califont) system costs $2,500 to $4,500 installed. A heat pump hot water system costs $4,000 to $7,000 installed but uses 60 to 70 percent less electricity than a standard electric cylinder. Solar hot water costs $6,000 to $10,000 installed.

The right system depends on your household size, energy source, and budget. Electric cylinders are the most common in NZ and suit most homes. Gas continuous-flow systems provide unlimited hot water and are ideal for larger families. Heat pump hot water systems have the lowest running costs — they extract heat from the air like a reverse fridge and can save $400 to $600 per year on electricity compared to a standard electric cylinder. Solar hot water works well in sunny regions but needs a backup element for cloudy days.

Most hot water cylinders in New Zealand last 15 to 25 years. Signs you need a replacement include rusty or discoloured hot water, inconsistent water temperature, leaking from the cylinder base, rumbling or popping noises, or the cylinder simply not producing enough hot water. If your cylinder is over 15 years old and you are calling out plumbers for repairs, replacement is usually more cost-effective. Upgrading from a low-pressure to a mains-pressure system also improves shower pressure throughout the house.

All hot water system installations in New Zealand must be done by a PGDB-registered plumber (or gasfitter for gas systems). The installation must comply with NZS 4603 for tempering valves — hot water must be stored at 60 degrees Celsius to prevent Legionella bacteria growth, but delivered at no more than 55 degrees at bathroom taps to prevent scalding. A tempering valve is required to achieve this. Your plumber must issue a certificate of compliance after installation.