The Federal Government Clean Energy Regulator states that the manual booster may only remain active for the single heat cycle until the target temperature is reached.
Both the compressor and the booster use the same logic but different temperature sensors. The compressor uses the lower sensor(top left number on the lcd) and when that sensor falls > the target temperature minus 11 degrees the compressor will start and heat to the target. Likewise the booster uses the upper sensor(centre number on the lcd) and when it falls > 11 degrees below the target it will start the single boost button and heat the top of the tank to the target. If you press the booster and it is within 11 degrees of the target it will switch itself off again.
Please also refer to the “When should i use the booster? – FAQ”
