3
SOLARcomfort systems are highly efficient and provide cost savings on
the energy used for heating hot water wherever they are used in the UK.
However, the savings made will depend on local climate, installation
characteristics and the households use of hot water.
It is important that the SOLARcomfort system is correctly sized for the
local climate condition and the household’s domestic hot water
requirements.
After installation of the SOLARcomfort system, changes to the
householders use of hot water will be beneficial. Simple changes such as
bathing in the evening instead of the morning, and putting automatic
washing machines on when free hot water is available by solar energy.
In addition, the timing of the dwelling’s boiler controls must be modified to
ensure the ‘hot water ON’ time is set so that the water temperature in the
cylinder is at a minimum by the start of the ‘solar day’.
The solar collectors are heated by the sun’s rays. The heat generated is
stored in a hot water storage cylinder e.g. an Ariston Primo twin coil stainless
steel cylinder. The AST 100 Solar Controller continually compares the
temperature of the water within the cylinder with the temperature of the
solar collectors.
Whenever the solar collectors are hotter than the water within the cylinder,
the controller switches on the system’s circulating pump. The temperature
differential between the collectors and the cylinder is set via the AST100
Solar Controller. The heat transfer fluid within the solar system is then
circulated through the collectors and the cylinder’s heat exchanger, heating
the cylinder in just the same way as a central heating boiler.
The cylinder typically has two coils (heat exchangers), the lower coil is
heated by the solar system, therefore solar is the primary heat source.
The upper cylinder is heated by an auxiliary heat source, typically a central
heating boiler, which is used to heat water when there is insufficient heat
generated by the solar system. The Ariston Primo twin cylinder also has
two immersion heaters making it suitable for electric only heating systems.
The SOLARcomfort system is a forced circulation sealed system and
therefore requires an expansion vessel and a pressure relief valve (PRV),
both supplied with SOLARcomfort.
The air separator with an integral air vent together with an automatic air
vent positioned at the highest point on the system ensures that the sealed
system remains free of air.
1.6 H
OW
T
HE
S
YSTEM
W
ORKS
See fig. 1.6A
1.4 SOLAR
COMFORT
1.5 L
IFESTYLE
