gledhill Stainless Lite HP SOL Indirect 180-400 litres Design, Installation & Servicing Instructions page 11

General Design Considerations
The cupboard footprint needs to be at least 650mm square for units up to 300 litres,
730mm for 400 litre units.
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 fi ttings on the cylinder should be insulated, and the unit should
NOT be fi xed 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 opposite, 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 boiler 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.
If two Stainless Lites are coupled together the secondary inlet and outlet pipes must
be balanced. The units must be fi tted on the same level.
Note: No valves must be fi tted between the expansion vessel and the storage
cylinder(s).
Combination Valve
I.V. I.V.
Page 11
INSTALLATION
The pipe connecting the boiler fl ow to the
appliance must not be less than 22mm
copper or equivalent.
Insulation of pipework
Pipe outside
diameter
15mm
22mm
28mm
35mm
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".
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 Stainless
Lite will function with lower inlet pressures, but
this will reduce the performance. There should
be a fl ow of at least 30 litres per minute or above
available into the property. Normally Stainless
Lite 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 .
INSTALLATION
Maximum
heat loss
7.89W/m
9.12W/m
10.07W/m
11.08W/m