The Low pressure cylinder is a horizontal system, so the water does not markedly stratify at the top in these systems as it does in a vertical cylinder, so there is no problem connecting the hot water outlet at the bottom. If the inlet is connected at the top of the cylinder, it will restrict the amount of water available at any one time as the water coming in to the system will not keep up with the water leaving.
The system is designed this way so that a large volume of water is not added at one time cooling down the heated body of water already in the system.
The system intake can also be restricted with a timer so that the cold water only comes in after early morning shower are taken. Then this new water has all day to heat up again ready for the evening.
Do you live in the Hobart area? Systems qualify for the 
