Califonts provide hot water only as its needed, this is seen as a benefit if you have little room for a hot water cylinder in your house or if you want to have an instant hot water supply. They burn gas to heat cold water instantaneously and it is then delivered straight to your tap. In NZ they typically use bottled LPG or natural gas from the mains line to your house.
Some pitfalls of an instantaneous gas water heater are:
- A limited flow rate, meaning that in some situations you can get fluctuations when multiple hot taps are used at one time.
- Natural gas is cheaper but has a monthly service charge so if there is nothing / very little else on gas then that cost has to be added in and voids quite a lot of savings.
- Any of course gas is a fossil fuel so they are burning fossilised sunlight which is contributing to the current climate crisis.
- They are often connected to LPG bottles which are no cheaper to run than a standard electric element.
An easy replacement or alternative to instantaneous gas is the Reclaim CO2 heat pump which can be installed outside with an outdoor hot water cylinder. No need to take up space inside your home.
The benefits of a CO2 heat pump include:
- Reducing running costs by at least 75% compared to bottled gas.
- Reduced environmental impact by utilising CO2 from the air instead of burning fossil fuels.
- The time in which you get hot water out of the tap will often be reduced (no start up cycle to go through, hot water just comes straight out of the top of the cylinder).
- The heat pumps are perfect for taking advantage of self-generated power from a PV system or cheaper & free power from off-peak tariffs.
The one disadvantage of a CO2 Heat Pump is the installation costs are a bit more than a gas instantaneous water heater but these will be paid back in a short time with the savings made by the system.
You may find it useful to use the EECA Water heating systems tool https://www.energywise.govt.nz/tools/water-heating/ which helps you see the different cost associated with the different systems and which one would suit you best.