Aquarian Thermo
installation instuctions
page 5
Important information
Siting
For optimum performance, with gravity fed systems, the distance between the bottom of the storage cistern and the shower
head should not be less than 1m (when using an adjustable height shower head). If using a fixed head, the highest point of
the pipe work must be not less tham 1m below the underside of the cistern. Please refer to the system layouts on the reverse of
this guide.
Pump installation
UNDER NO CIRCUMSTANCES MUST A PUMP BE FITTED DIRECTLY TO THE WATER MAIN.
A pump must only be used to boost the pressure from tank-fed supplies. A typical layout is shown on the reverse of this guide.
Stored water capacities
The minimum capacity of the cold storage cistern should not be less than 225 litres (50 gallons). The capacity of the hot
cylinder must be capable of meeting the anticipated demand.
Pressures
The Aquarian Thermo shower valve is designed to control static pressure up to 10 bar. Where pressures are likely to exceed 10
bar, a pressure reducing valve (PRV) must be fitted into the incoming mains supply. A setting of 3 bar is recommended. It
should be noted that daytime pressures approaching 8 bar can rise above the stated maximum overnight.
The Aquarian Thermo is not suitable for mixed supply systems e.g. gravity hot and cold mains.
A suitable PRV is available from Aqualisa.
Gravity fed hot and cold supplies
The cold supply for the valve assembly must be taken directly from the cold storage system. The hot supply may be taken from
the vent/draw off pipe of the hot water cylinder at a point below the cylinder connection or alternatively from the underside of
the horizontal draw off.
Rising pipe work must not be connected into the horizontal draw-off from the cylinder or to any point in the vent/draw off pipe
above the cylinder connection.
CYLINDER TEMPERATURE IN EXCESS OF 65ºC MAY RESULT IN POOR SHOWER PERFORMANCE.
To minimise pressure loss we recommend that the hot and cold supplies are run in 22mm as close as reasonably possible to the
mixing valve before reducing to 15mm.
A typical layout is shown on page 17.
Balanced high-pressure system
The Aqualisa Thermo cartridge is designed to operate with unvented hot water storage systems up to a maximum pressure of
10 bar. A PRV must be used if either supply exceeds 10 bar. The cold water supply must be drawn from the same mains supply
as that to the hot water system (down stream of the cylinder manufacturers pressure limiting valve, where supplied) and the
hot supply from the nearest convenient draw off point. Account must be taken of pressure drops that may occur when other
draw-off points are used while the shower is in use.
Pipe work can generally be run in 15mm.
A typical layout is shown on page 17.
Combination boiler/multipoint system
The gas water heater must be capable of raising the temperature of the incoming water by 35ºC and delivering a flow rate of
no less than 9 litres (2 gallons) per minute to the shower valve. This is sufficient to operate one outlet point at a time. The
Aqualisa Thermo cartridge is designed to operate from the mains at a maximum of 10 bar. If the mains pressure exceeds 10
bar a ‘drop tight’ PRV must be fitted on the supply pipe after the main stopcock.
The cold supply can be taken from the nearest convenient mains supply and the hot supply can be taken from the nearest hot
water draw-off point. Account must be taken of the pressure drops that will occur when other draw-off points are used while
the shower is in use.
Pipe work can generally be run in 15mm.
A typical layout is shown on page 17.
