18
Pre-installation
Installation
PumpWise guidelines
General specification
Trouble shooting
PumpWise and warranty
Pump hunting protection
In negative head systems all the discharge
pipework after the pump is pressurised. In
such systems there exists the possibility the
pump will hunt ON-OFF-ON etc at intervals.
This will happen:
• if all outlets are not fully closed
• if there is a leak at a connection
• if boosted toilets are not fitted with
equilibrium ball valves
• or as residual hot water contracts in long
pipe runs.
The irritating effects of hunting are
cushioned by the pressure vessel which is an
inbuilt feature of the Right pump universal
range.
Stored hot water volume
In calculating the volume of the stored
hot water requirement it is important to
consider:
• number of bathrooms, with particular
attention to the size of the bath
• number of persons in household
• time spent in shower e.g. 10mins in a
5 gall/minute shower will use up 50
galls/227 Litres of the cold water storage
capacity approx 60% of which (30
gallons/136 Litres) will be hot water from
the cylinder.
Stored hot water temperature
Extract from BS5546:1990 (Current)
“The mean temperature of the stored water
should not normally exceed 60°C and in
a combined central heating and domestic
hot water system it is recommended that
the stored water temperature is controlled
independently from that on the primary
circuit”.
Extract from BS6700:1997
“Under normal conditions the
temperature of stored hot water should
never exceed 65°C. A stored hot water
temperature of 60°C is considered sufficient
to meet all normal requirements and will
minimise scale deposits in hard water areas”.
Effective control of stored hot water is simply
achieved by use of a cylinder thermostat and
zone valve or direct acting thermostatic valve
(e.g. tapstat).
In systems where the stored hot water
temperature is not controlled eg Aga solid
fuel appliance or very crudely by the boiler
thermostat, use a HWS Blending valve
controller.
HWS Blending valve controller
The HWS Blending valve controller is
designed to protect booster pumps in
systems where the temperature of the stored
hot water is uncontrolled.
x175810_Salamander_p4_vw.indd 18 30/03/2017 15:06
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