3
Alpha SolarSmart 100 - User Instructions
The boiler domestic hot water ther
mostat
must
always be set to the maxim
um setting. A label has been supplied which should
have been positioned adjacent to the domestic hot w
ater thermostat knob
, as shown in Fig.
2, to ensure the maximum setting is
maintained.
Fig. 2
WORKING PRINCIP
AL - Fig. 3
The solar
collector uses
the energy
of the
natural
light to
heat the
water
being circulated
around the
collector. When
the heated
water
enters the
drain
back
unit, heat
is tr
ansfer
into the
stored w
ater via
a heat
exchanger
. Stored
domestic hot
water
is pumped
from the bottom of the solar cylinder through the drain bac
k unit heat exchanger where it is heated and retur
ned to the cylinder.
When a hot water tap is tur
ned on mains water flo
ws into the bottom of the solar cylinder and hot water flo
ws out of the top
tow
ards the boiler. If the boiler inlet sensor detects that the w
ater from the cylinder is above 60°C the w
ater flows directly through
the boiler to the tap, if the temper
ature is less than 60°C the boiler heats up the water
. When the flo
w is less than 60°C the water
temperature is maintained b
y the boiler.
As the temperature of the w
ater entering the boiler is higher than the nor
mal incoming mains water
, less gas is required to heat
the water to the set temper
ature of above 60°C thereb
y saving energy costs
.
Fig. 3
OPERATION OF
THE SOLARSMART SYSTEM - Fig.
3
When the controls detect a collector sensor temperature that is at least 10°C higher than the lo
wer cylinder sensor and the solar
cylinder temperature is less than 65°C
, the drain bac
k unit pump will start to circulate w
ater around the collector. At the same
time that the drain bac
k unit pump starts the cylinder pump will star
t at 16% full speed to circulate the cylinder water through
the drain bac
k unit heat exchanger
. The dr
ain back unit pump will stop when the temper
ature difference betw
een the collector
sensor and the low
er cylinder sensor falls to 3.5°C or the cylinder temper
ature reaches 70°C. The cylinder pump will contin
ue to
run f
or 120 seconds to collect any e
xcess heat from the drain bac
k unit then it will also stop.
When the pumps are operating, a flashing pump symbol will be visib
le in the display (Fig.
1). If a f
ault occurs, a f
ault code will be
visible in the displa
y.
3
POSITIONING OF THE COLLECT
OR
4
SYSTEM OPERATION
The solar
energy supplied
by
a system
var
ies with
the or
ientation and
tilt of
the collector
, which
will usually
be deter
mined by
the existing
roof. Ho
wev
er, the
predicted var
iation is
slight. F
or a
collector facing
anywhere
between
SE and
SW
and tilted
between
15° and
75° from
the horiz
ontal
, the annual solar energy supplied will be at least 90% of that obtained at the optim
um collector position
(South at 30°).
It should be remembered that shading from trees, b
uildings etc., can produce a significant decrease in system perfor
mance, and
collectors should be positioned to minimise shading from the sun.
bar
0
4
3
2
2.5
3.5
1.5
0.5
1
CORRECT PRESSURE
WHEN COLD
RESET
INFO
RESET
BOOST
bar
°C
x100rpm
IMPORTANT
MUST
This Combi boiler is fitted to an
Alpha Solar system and the domestic
hot water thermostat
always be
set at maximum
Cold water inlet
Cold water to DBU
Alpha InT ec boiler
Warm water
to boiler inlet
Cold water supply if using
thermostatic mixing valve
Hot water
to taps
Thermostic
mixing valve
Hot water from DBU
Solar cylinder
(case not shown)
Drain back unit
(DBU)
Solar
collector
Collector
sensor
DBU pump
DBU heat
exchanger
Cylinder sensors
Control unit
Drain
point
System pump
T emperature/pressure
relief valve
Inlet sensor
Pressure
relief
valve
