Pressures
The cartridge is designed to operate from the mains at a maximum of 10 bar. If the mains pressure exceeds 5 bar a
‘drop tight’ PRV must be fitted on the supply pipe after the main stopcock. A setting of 3 bar is recommended. It
should be noted that daytime pressures approaching 8 bar can rise above the stated maximum overnight.
A suitable PRV is available from Aqualisa.
! This product is not suitable for mixed supply systems, e.g. gravity hot and mains cold.
Combination boiler/multipoint system
The product is suitable for use with combination boiler systems. The combination boiler MUST have a minimum
rating of 24kW (80,000 Btu) and be of the type fitted with a fully modulating gas valve. This is sufficient to operate
one outlet point at a time.
If in any doubt, please contact the appliance manufacturer before installation commences.
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. A typical layout is shown overleaf.
Balanced high-pressure system
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.
A typical layout is shown overleaf.
Boosted gravity fed hot and cold supplies
Services must be installed according to good plumbing practice having regard to pipe sizing, long pipe runs and
low-head situations.
Pump installation
PLEASE REFER TO THE MANUFACTURERS PUMP INSTALLATION GUIDE FOR PUMP INSTALLATION
INFORMATION.
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 overleaf.
A minimum 1 bar twin ended booster pump may be fitted with the mixer shower, but for improved performance,
we recommend a twin ended booster pump larger than 1 bar is used.
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.
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 to suit the intended inlet connection fittings.
Siting
With boosted gravity fed systems, please ensure the minimum gravity flow rate is sufficient to operate the pump flow
switches.
PLEASE REFER TO THE MANUFACTURERS PUMP INSTALLATION GUIDE FOR PUMP INSTALLATION
INFORMATION.
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