EcoSolar Energy Conscious Design Limited
27
General Installation
Pipework
All pipework shall be copper and completed in a neat and economical layout, using long radius
bends and minimising the use of fittings to ensure that the resistance to flow rate through the
pipework is minimised. Pipework shall run straight and true, at a constant grade and parallel to
adjacent surfaces. Pipework joints shall be located a minimum of 75mm from walls, beams and
floors.
For single and two solar collector installations the flow and return pipework between the solar
collectors and hot water cylinder shall be a minimum of 10mm diameter. Systems consisting of
three to four solar collectors shall be piped up with 15mm copper pipework. Solar collectors
shall not be piped up together in more than banks of four.
Thermosyphon systems shall be a minimum of 20mm diameter only if the solar collector is
within a couple of meters of the cylinder and locations are optimal for thermosyphon action
else, 25mm pipework shall be installed. All pipework shall be adequately supported, supports
shall also be installed immediately either side of pumps, valves and changes in direction. All hot
water pipework is to be insulated using Armstrong Armaflex or similar.
Pipework shall be flushed out to ensure no foreign matter remains in the system.
The pipework shall be pressure tested to 1.5 times the working pressure of the system or
1000kPa which ever is greater.
The pipework shall be filled with the air release valves open to ensure all air is removed from
the system.
The solar collector shall be located as close as possible to the hot water cylinder to minimise
pipework lengths.
NOTE Use PTFE tape to seal the fittings, do not use hemp as this can exert extreme
stresses on the fittings which are not covered by any guarantee and can dry out causing
leaks.
Long pipe runs shall incorporate expansion loops or bends to allow for thermal expansion.
These shall be installed horizontally to avoid forming air locks.
The pipework should be installed such that;
•
The flow, colder water, to the solar collector is connected from the bottom of the
hot water cylinder to the bottom of the solar collector.
•
The return, warmer water, from the solar collector is connected from the top of the
solar collector to the top of the hot water cylinder or dispersion tube.
