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General Design Considerations
The cupboard footprint needs to be at least 730mm square for units up to 300 litres.
The base chosen for the cylinder should be level and capable of supporting the weight
of the unit when full of water as shown in General Data. The discharge pipework for the
safety valves must have a minimum fall of 1 : 200 from the unit to a safe discharge point.
All
exposed pipework and fittings on the cylinder should be insulated, and the unit should
NOT be fixed in a location where the contents could freeze.
In new systems, pipes should be insulated to comply with building regs, the maximum
permissible heat loss is indicated in the table below, and labelled accordingly as follows:
i. Primary circulation pipes for domestic hot water circuits should be insulated
through their length, subject only to practical constraints imposed by the need
to penetrate joists and other structural elements.
ii. All pipes connected to hot water storage vessels, including the vent pipe, should
be insulated for at least 1 metre from their points of connection to the cylinder (or
they should be insulated up to the point where they become concealed).
In replacement systems, whenever a heat pump or hot water storage vessel is replaced
in an existing system, any pipes that are exposed as part of the work or are otherwise
accessible should be insulated as recommended for new systems, or to some lesser
standard where practical constraints dictate.
The pipe connecting the heat pump flow to the appliance must not be less than
22mm copper or equivalent.
Further guidance on converting heat loss limits to insulation thickness for specific
thermal conductivities is available in TIMSA “HVAC guidance for achieving compliance
with Part L of the Building Regulations”.
INSTALLATION
INSTALLATION
Mains Water Supply
Existing properties with a 15mm supply will be
satisfactory provided the local mains pressure
is good, but should be confined to single
bathroom properties. For new properties where
simultaneous demand is required to more than
one bathroom or a bathroom and one or more
en-suites, the communication and service pipe
into the dwelling should be a minimum of 22mm
(usually in the form of a 25mm MDPE supply).
The optimum performance is achieved if the
inlet pressure is 3 bar dynamic. However, the
Aquarea will function with lower inlet pressures,
but this will reduce the performance. There
should be a flow of at least 30 litres per minute
or above available into the property. Normally
Aquarea provides well in excess of 40 litres/min
in most conditions. Flow rates for ALL mains
pressure systems are subject to district pressures
and system dynamic loss. Particularly on larger
properties with more than one bathroom, the
pipe sizes should be calculated in accordance
with
BS EN 806-3:2006 and BS 8558:2011.
Insulation of pipework
Pipe outside diameter
Maximum heat loss
15mm
7.89W/m
22mm
9.12W/m
28mm
10.07W/m
35mm
11.08W/m
