Functional Description - Defensor Mk4 Mode D'emploi

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Functional description

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Open the fold-out page to display the general unit survey for the functional
description!
The Defensor Mk4 steam humidifier is an unpressurized steam generator for
ventilating and air-conditioning systems. In conjunction with a steam distribution
head "Process" (accessories "Z257"..."Z260") the unit may be used for process
humidification, or for direct room humidification using a ventilation unit (options
"Z217" and "Z218"), respectively.
The Defensor Mk4 operates on the resistance heating principle and is therefore
suitable for operation with untreated water, VE-water (fully demineralized water)
and E-water (softened water TH0). The steam production can be regulated fully
variably with an external continuous regulator or with the internal regulator (on "IT"
units).
Note: A humidistat (option "HDU3") can be connected via a step control board
(option "Z243") for 3-stage regulation.
Water supply
The water (untreated water, VE-water, E-water) is taken via an optional filter valve
(accessory "Z261") to the steam humidifier. It reaches the steam cylinder via the
inlet valve (level controlled) and the filling cup.
Level regulation
The water level in the steam cylinder is continuously monitored with the level unit.
If the water level reaches a preset level (owing to the evaporation process) the level
unit supplies a signal to the controller. This opens the inlet valve and the steam
cylinder is filled up. When the preset operating level is reached, the level unit
supplies another signal to the controller to close the inlet valve.
The pressure equalizing pipe between the steam connection and the level unit
ensures that the water levels are the same in the steam cylinder and the level unit.
Steam generation/regulation
The steam is produced in the steam cylinder by several resistance heating elements.
An external (on "ST" units) or the internal regulator for connection as required (on
"IT" units) control the steam production fully variably from 0 to 100 %.
Flushing
The evaporation process increases the concentration of minerals in the water. A
suitable volume of water must be flushed through the steam cylinder from time to
time and replaced by fresh water to ensure that this concentration does not exceed
a specific value harmful for operation.
The Mk4 steam humidifier performs an auto-adaptive flushing. This consists of the
following two forms of flushing:
- Automatic flushing:
Automatic flushing takes place as soon as the water in the steam cylinder
exceeds the upper operating level (e.g. by foaming of the water).
Flushing dependent on time:
-
The time-dependent flushing performs the flushing process at preselected time
intervals (see separate documentation "Electrical Installation", red sheets).
Automatic or time-dependent flushing takes place depending on the water quality
and the operating data.
The drain valve and the inlet valve are opened simultaneously for flushing. After
expiration of the preset flushing time (factory setting, cannot be changed) the drain
valve is reclosed.
If the lowest operating level is reached during the flushing process, the inlet valve
remains open until the water level in the steam cylinder has reached the normal
working level again. If the lowest operating level is not reached, the inlet valve is
closed.