Mark GSW+ 30, Technical Manual

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1.3 Operation
The gas-fired condensing air heater of the GSW+ series are intended for the heating of industrial and
related areas. The GSW+ air heaters consist of a gas-fired boiler and a hot water coil, placed in the
airflow. The air that is blown in by the fan will be heated by the coil. This technique provides a perfect
homogeneity of the air temperature. Unlike a conventional air heater, the partial or complete restriction of
air flow or an interruption of the electrical power during operation will not damage the unit.
The combustion section is completely isolated from the air circuit, which makes it impossible for the
system air to mix with the combustion gases. The unit is equipped with a burner with low Nox emissions.
The combustion air is sucked in by a fan with a variable flow rate.
The air is sucked in by a venturi system. This system makes sure that the gas and air over the entire range
are in the right proportion. The air/gas mixture is fed to the burner, located in the middle of the boiler.
The flame and fumes will go through the heat exchanger twice to give off maximum power. Thanks to
this technology, an efficiency of at least 98% at the maximum loads and 108% at full modulation can be
achieved. The optimization of the performance of a condensation system is influenced by its controls. The
lower the power output of the air heater, the greater the condensation and thus the higher the efficiency.
The modulation range of the GSW+ is 30% of the maximum load.
The electrical control of the air heater is connected to the room thermostat. The control device provides
the continuous modulation of thermal power.
The modulating effect of the GSW+ heater guarantees perfect adaption to the real heat demand of the
building. In versions equipped with fans with a variable flow rate, one can also vary the air supply.
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