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Running your hot water system can be expensive, especially when you’re not there – but turning it off can be dangerous. Find out when you should turn your hot water off.
Remembering just how much energy your hot water system consumes (up to roughly 25% of your electricity bill in the case of an electric storage heater), you can save a lot of money and prevent waste by controlling when it’s used and how.
If you’re planning a holiday, for example, turning off your hot water system while you’re away will ensure that it isn’t wasting gas or electricity when you’re not there. The same might apply if you’re doing renovations, and if you have a summer home or beach house it’s very important to remember to turn off the hot water when nobody is there.
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Solar booster systems
By law, all solar hot water systems in Australia must incorporate some sort of booster, typically fuelled by gas or electricity. The booster is set to heat up the water when it drops below a certain temperature but this is not necessary when the hot water is not going to be used for extended periods of time.
The booster doesn’t need to be used if it is not needed, but the water you use should be heated to 60°C to kill off any bacteria present in the water, so you may need to engage the booster once per day depending on how hot the water is getting in your system.
Most boosters come with some sort of manual cut off switch that allows for manual operation. If there isn’t, then for electric systems, it is still possible to switch it off at the fuse. For gas boosters, you can shut off the gas supply, but you may need to relight the pilot light afterwards.
Advanced solar booster control
If you really want to take full control of your booster, pay close attention to the weather. You may need to engage the booster during cold weather spells, but you can successfully operate a solar hot water system without it during warmer weather.
Use your hot water in the mornings; this gives the water in your collectors the most amount of time to regenerate. If you also keep the bulk of your hot water usage to the weekends, you should be able to turn off the booster during the week. Be sure to turn it back on again if you get a couple of overcast days in a row as this will reduce the amount of available sun for heating your water.