What size system suits your household?
Working out the right size for your new hot water system is one of the most important aspects of system selection. Sizing is a trade-off between cost and performance, and a key element of performance is the level of risk of running out of hot water!
The system should be sized for the dwelling, not necessarily its occupants. People sell houses and move on, but the hot water system stays.
It is generally accepted that each person will use around 50 litres of hot water per day, and in a storage system it is good to have 1.5 days capacity. A three-bedroom house can comfortably accommodate four people and so it should have a 300-litre tank, even though it may currently be occupied by a retired couple.
Also think about whether the dishwasher and washing machine need plumbed hot water. These appliances often include in-device water heating these days, which reduces household hot water storage requirements.
What type of tank should I consider?
A mains pressure tank is common for both solar and heat pump hot water systems.
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