Copyright © 2014
Ikhwezi Solar (Pty) Ltd, Novatherm CC, Solar Assist (Pty) Ltd
3
Assess site specific risks and eliminate or reduced to an acceptable
level so as to satisfy health and safety requirements, prior to
installation.
Water temperature can reach boiling point and the collector can reach
stagnation temperatures of over 70°C. Shade collectors during
installation to prevent heating.
Take care when handling collectors to prevent breakage to glass and
injury. Safety goggles, work wear and gloves must be used to reduce
risk of injury.
Be aware of overhead power lines coming in through roofs, as well as
electrical wiring running through ceilings.
Assess weather and postpone roof work if unsafe (e.g. high winds,
rain, lightning, etc.).
Scaffolding and safety equipment must be installed by certified
personnel and signed-off accordingly. Inspect before use.
Inform home owners or building occupants of time and place of work
to be carried.
Ensure occupants are aware of site access constraints and all health
and safety implications relevant to them. Cordon off the area, if
applicable, to prevent personal injury and ensure any pets are
secured.
Ensure personnel working on installation are competent and in suitable
physical condition. Installers must be trained and conversant with the
assessment of height hazards, working at height safety procedures,
assessment of safety equipment (e.g. scaffolding, harnesses, etc.) and
the use and wearing of safety equipment (e.g. goggles, hard hats,
gloves, etc.).
All personnel working on the installation of a solar hot water system
must be issued with the appropriate safety equipment and be trained
in their use.
Failure to observe
safe practices may
result in:
scalding /
burns;
electrical
shock;
and/or falling,
which can cause
serious injury or
death.
4.
System configurations
4.1
Novasun Thermosiphon System
For the purposes of the Eskom Rebate Program only thermo-siphon systems
can be installed and a rebate claimed.
A thermo-siphon system relies on the natural circulation of fluid between the
collector and the geyser. In order for the thermo-siphon process to occur
the geyser must be placed in a higher position than the solar collector. The
system operates according to the laws of thermal dynamics (i.e. a liquid,
when heated, becomes less dense and rises above the denser cooler liquid).
Heated water rises up through the collector and into the geyser, displacing
colder water therein, which sinks to the header pipe of the Novasun
collector. The process continues until the collector can add no more gain in
temperature or until the sun stops shining. Without sunlight the water in the
collector header pipe cools, becomes denser, preventing hotter liquid in the
geyser from being displaced.
A thermo-siphon can be close-coupled or split as illustrated below, provided
there is sufficient roof space.
4.2
Novasun Split-pumped System
•
Where the solar water heater is installed in the roof, it must be
installed in compliance with SANS 10106 complete with a Safety Valve,
drain cock, Multi Pressure Control Valve 400kPa, Drip Tray and vacuum
breakers on the cold and hot water supply.
•
When installed inside the roof minimum clearance must be allowed in
order to remove the element and thermostat.
•
Roof structural integrity must be handled according to section 6.5.
•
For Product warranty detail refer to the separate Warranty Agreement.
•
Pump Circulation in the Novasun SWH system.
•
When it is not convenient or possible to place the cylinder higher than
the collector, a circulating pump controlled by an electronic control unit
and two sensors is used to monitor the temperature of the manifold
and the cylinder, that enable the powering of the circulation pump
when the water in the panel manifold is hotter than the water in the
cylinder.
•
When the temperature difference is less than the set point the pump
will stop
•
When temperature of water in the cylinder reaches the highest set
point, the controller will stop the pump.
•
The circulating pump used must be installed and maintained according
to the manufacturer’s instructions.
•
A 12V circulating pump with a photovoltaic can also be used.
•
A split-pumped system is illustrated below.