The system solutions are only suggestions and may, of
course, need adapting to your property, needs and conditions. The
solutions are designed for 750 litre tanks, but the system can
obviously be used with other models. We recommend you hire a
professional (i.e. a plumber) to carry out the
installation.
Dalatanken with pellet boiler and solar
energy
Click on the image to enlarge.
The tank is the centre of the heating system. The boiler is
connected such that it works on the tank's upper part, whilst the
solar energy is used for the tank's lower part, via the solar
energy coil. By adding an extra pair of valves, you can switch
between letting the boiler heating up only the upper part of the
tank, or the entire volume. (Winter and summer settings)
The boiler is controlled by a thermostat inside the tank that tells
it when it needs to start up. As hot water rises, the heat from the
solar energy coil at the bottom of the tank will heat up the entire
volume once enough heat has been gathered from the sun. Therefore,
the boiler will only start up if the solar energy is
insufficient.
The heat to the radiators (or under floor heating) is provided by
the tank through a bivalent bypass valve that first releases the
hot water from the middle of the tank that has been mainly heated
using solar energy. Once the heat from the middle begins to run
out, the bypass engages and begins to mix in the heat from the top
of the tank.
The hot water is prepared in two steps, using two gilled tube
coils. By connecting the hot water socket with two mixing valves,
the heat is first taken from the lower part of the tank (heated
using solar energy), which enables the solar energy coil to
proportion more heat to the tank. The lower the temperature around
the solar energy coil, the bigger the temperature difference in the
solar panels, resulting in a higher solar energy exchange.
The solution using the bivalent bypasses, double hot water coils
and two cleverly connected mixing valves is a way to prioritise and
make the most of the free energy provided by the sun and make
savings by using less heat produced from purchased fuel.
Dalatanken with wood fired boiler and solar
energy
Click on the image to enlarge.
The accumulator tank plays an important and central role when using
wood fired burners. There is a legislative requirement that new
installations should have an accumulator tank when using wood fired
burners, but even existing installations benefit significantly from
them with cleaner combustion, less pollution, improved
effectiveness and, not least, much more comfort. Combining a wood
fired system with solar energy results in a significant practical
improvement, with likely savings of 20-25% in annual fuel
volumes.
A wood fired system requires a significantly larger accumulator
volume than a pellet boiler. A good system should be able to store
enough energy for at least a day's use during the winter and the
tanks should be able to receive at least the energy resulting from
a full load of wood logs. Firing up the boiler more than once a day
should only happen in exceptional circumstances.
The size of the boiler should also be suitable to enable you to
fire up the tank between coming home from work and going to bed for
the night. A modern boiler can do that with one or two loads of
wood logs.
In almost all cases, the tank capacity should be at least 1,500
litres, although a higher capacity certainly won't hurt as the
higher it is the larger the margins and the less often the boiler
will need to be fired up.
We can provide tanks in most sizes, with the most common being the
750 litre tank. This is because it is often difficult to bring in
larger tanks through the doors and corridors leading to the boiler
room. The 750 litre tank has a diameter of 75 cm and will fit
through most normal doors.
The system solution shows a combi installation that has wood
firing, solar energy and a back up electrical option. The solution
consists of a technical tank with coils for solar energy and hot
water. This then connects to the number of slave tanks required to
achieve the desired volume.
To get a "satisfactory" volume for the solar panels during the
summer, the slave tanks can be switched off, or a directed valve
can be installed that opens the connections between the tanks when
the solar energy tank is fully heated. An even better option is to
install a 4 coil tank instead of the split, 3 coil tank. This
allows you to have the slave tank connected, yet still have usable
hot water from solar energy, as it starts with the upper solar
energy coil, heating the tank's upper part before activating the
lower solar energy coil until all the tanks are fully heated.
The same principle holds for the hot water socket as in the pellet
boiler above.
Dalatanken 4 coils
Click on the image to enlarge.
The system for the 4 coil tank is the same as for our standard 3
coils tank. The difference is that it contains an extra solar
energy coil in the upper part of the tank.
When the solar panels begin to work, there is naturally a delay
before the temperature reaches a level where the hot water can be
used. This is much quicker in the 4 coil tank as the solar energy
is channelled to the upper coil and only once the water at the top
of the tank is warm does the system switch and continue to heat the
bottom part. Therefore, it is not necessary to wait until the
entire tank has heated.
This solution is more economic the greater the capacity, as the
volume is larger, with a longer heating time.
Further Connection Suggestions
Let the sun's energy heat the pool
Click on the image to enlarge.
Kitchen boiler and solar energy
Click on the image to enlarge.
