Rotex GasCompactUnit Series, Инструкция по установке и обслуживанию

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2.1 General function
Fig. 2.1.1 on page 6 indicates the equipment
GSU layout in diagrammatic form. Fig. 2.1.2 on
page 7 shows the GCU in diagrammatic form.
Tab. 2.2.1 summarises the legends used in the
figures.
The ROTEX GSU/GCU is a gas fired condensing
boiler (A), that is integrated in a 500 litre DHW
cylinder (B). The DHW cylinder is filled with
unpressurised water (C).
Inside the cylinder is a spiral heat exchanger
made from a corrugated stainless steel pipe
(18) that is drawn from the cylinder floor to the
top. This generates the required domestic hot
water.
When there is sufficient sunshine, the DHW
cylinder of the GSU can also be heated with
solar power (accessories – ROTEX Solaris).
When the available solar energy is
insufficient, the gas fired condensing boiler
will reheat the cylinder water via a corrugated
stainless steel pipe heat exchanger (19),
through which the heating water flows from
top to bottom.
When heating with the gas fired condensing
boiler of the GSU, deliberately only the upper
zone of the cylinder is held at the selected
temperature. Subject to the available solar
energy, the entire cylinder can be heated with
solar power, ensuring that the stored energy is
utilised both for DHW heating and for central
heating backup.
The boiler is integrated in the DHW cylinder,
consequently there are no surface or
cool-down losses. The heat is completely
transferred to the cylinder water and not to the
ambience. In addition, the excellent thermal
insulation of the plastic cylinder ensures
minimum thermal losses.
The GSU is split into 3 zones :
Zone 1 (upper zone): DHW zone (D)
Zone 2 (lower zone): Solar zone (E)
Zone 3: Central heating
backup (open zone (F) thermally
insulated (towards the
area inside zone 1) bottom)
The GSU can provide comfortable hot water at
any time. Simultaneously, solar energy can be
stratified for DHW heating and central heating
backup. The large (500 litres) capacity of the
cylinder also enables the bridging of longer
times without sunshine.
With the GCU, the entire cylinder content is
designed as DHW zone to make the highest
DHW output available. Any associated thermal
utilisation of solar energy is recommended in
conjunction with a Solaris system (pre-heat
stage) upstream of the GCU.
The arrangement and flow pattern of the heat
exchangers creates a distinct temperature
stratification on all devices. That results in
higher energy yields.
The output is variably regulated by the
electronic control units GSU 25 (GSU 35)/GCU
25 (GCU 35), modulating from minimum 5 (8) to
maximum 25 (35) kW. The GSU/GCU flexibly
matches its output to changing conditions.
The internal microprocessor control manages
the output.
The flue gas temperature remains below 90 °C
at all times.
The energy contained in the fuel gas is utilised
to its optimum by the condensing technology.
In this process, the flue gas inside the boiler
and - with balanced flue operation - in the flue
gas system cools down so far, that it drops
below the dew point. This condenses a part of
the water vapour created as part of the gas
combustion. Contrary to low temperature
boilers, the condensing energy is transferred
to the heating system, enabling efficiencies in
excess of 100 % to be achieved.
A very flat cylindrical aluminium boiler body is
let into the cylinder lid. The combustion
chamber is arranged in the centre. The flue
gas is swirled around the combustion chamber
and then channelled through the top.
Any condensate created by this process is
collected at the lowest point of the boiler body
and channelled, via a plastic pipe, into the
cylinder, where it is neutralised.
From there it is routed via the cylinder
overflow into the drain.
At the GSU, a further heat exchanger is
connected via a flange in the lower part of the
boiler. It is arranged inside a tubular thermal
insulation sleeve, that is open at the bottom.
This heat exchanger can, when solar energy is
being utilised, transfer solar energy to the
heating network, subject to there being
sufficient solar irradiation. This enables the
effective solar backup of this heating system,
particularly during spring and autumn.
The ROTEX GasSolarUnit/GasCompactUnit has
been designed so that it can operate in
balanced flue mode. In that case, the required
combustion air is drawn by the burner from the
outside through the installation duct or a
concentric flue.
That has many benefits:
- The installation room requires no ventilation
aperture to the outside and therefore does
not cool down.
- Low energy consumption.
- Dust, solvents, washing powders etc. are not
drawn in by the burner. The room can be
used as laundry room, workshop and similar.
- The system may be installed as attic heating
centre.
- Additional energy yield in the flue through
preheating the combustion air.
The GSU/GCU is managed by a fully electronic
digital control unit in conjunction with the
“intelligent” burner control unit. The multi-
language plain text display and the key pad
are clearly integrated into the upper part of the
GSU/GCU. This enables the checking of all
operating parameters, which may also be
modified by your heating contractor. The
integral control unit offers many easy,
convenient operating options.
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C h a p t e r 2 : G e n e r a l f u n c t i o n a n d
c o m p o n e n t d e s c r i p t i o n