What's the difference between positive and negative head shower pumps?
Simply so, do I need a positive or negative head shower pump?
If the shower is more than 600mm, about two rulers, below the cold water tank, then you need a positive head shower pump. If the shower is less than 600mm below the cold water tank, then you need a negative head shower pump.
Also to know is, what does negative head shower pump mean?
The term 'negative head' means the cold water tank outlet is below or near-level with the shower head. Negative head pumps have a pressure switch to recognise when the shower is turned on even when water is not flowing.
A positive head system occurs when there is more than 600mm from the bottom of the cold water tank to highest point in the system. A negative head system occurs when the distance from the bottom of the cold water tank to the highest point in the system is less than 600mm.