Hot water systems: what's the right size?


To work out whether a hot water system suits your purposes you need to consider a few issues. The first involves determining what size and heating capacity you need. There are different things to look for when comparing a storage tank water heater with a continuous flow one but both depend on how much water you expect your household to use at maximum demand. Likewise, when considering a solar hot water system, the demand for hot water will dictate how big your collector area needs to be.


What to look for in a storage tank system

Capacity and demand 
The things you need to consider will depend on the type of system you choose.

There are two main things to look for in a storage tank system; the volume of the tank, and the capacity of water it can deliver when you need it most.

The tank’s volume does not need to be the same as how much it can deliver at once. For example, if you have a 50 litre (L) tank and use 75L per day, you might assume that your tank would be too small. If that 75L consists of using 25L of water 3 times throughout the day though, the tank is in excess of what you require.

Bigger tanks take more energy to heat, so enhancements like thicker tank insulation help to ensure that the burner or element is not working too hard to keep water hot when you’re not using it. Don’t be fooled into thinking that it’s as simple as saying that a smaller tank will consume less power, though. Always check the energy efficiency rating and install the system with the highest star rating you can find and af