General Function Of Series Hsg - Ehrle HSC 723 -ST Betriebsanleitung

Hochdruck-Reinigungs-Systeme High-Pressure-Systems
1.5.3

General function of series HSG

The water from the water system fl ows through the water inlet (01) to the fl oat
container (02), when the trigger gun (17) is activated (see fi gure 5).
The high pressure pump (05) absorbes the water from the fl oat container (02)
through the low pressure injector (04). The high pressure pump (05) pressuri-
zes the water to the adjusted operating pressure.
The pressure switch (07) monitors the operating pressure. It switches on the
high pressure pump (05), when the pressure exceeds 25 bar.
When the trigger gun (17) is activated, the water is pumped through the
unloader valve (08). This is an adjustable control element for reducing the
operation pressure.
After the non return valve (09), which is integrated in the unloader valve (08),
the pressure gauge (10) indicates the operating pressure. The pressure switch
(11) switches on the High Pressure Cleaner, when the trigger gun (17) is
activated and the pressure is under a threshold of 25 bar.
Depending on the chemical metering valve (20) setting the cleaning detergent
may be admixed to the water from one of two external connected cleaning
detergent containers (18 or 19).
The chemical low pressure injector (04) causes a suction in the cleaning deter-
gent path, when the high pressure pump (05) is activated and the chemical
metering valve (20) is opened. The resulting underpressure sucks the cleaning
detergent and admixes it through the low pressure injector (04) into the water
circuit. The chemical metering valve (20) provides also the cleaning detergent
dilution adjustment. Whithout underpressure, the non return valve (21) sepea-
rates the cleaning detergent circuit from the water circuit.
The gas is fed through the gas supply pipe (12) to the gas burner (26). The
heat exchanger (14) warms the water in the water boiler (25). With the ther-
mostat (03) the water temperature may be set to the desired temperature
vaue.
When exceeding the determined temperature threshold in the boiler, the maxi-
mum thermostat (15) switches off the High Pressure Cleaner.
The fl ame monitor (23) switches off the High Pressure Cleaner, if failures
occur. The High Pressure Cleaner is switched off by the monitoring for pump
temperature (22), when the high pressure pump exceeds the allowed tempera-
ture threshold value.
For High Pressure Cleaner protection the water is led to the water boiler (25)
via the bypass path (27), when the trigger gun (17) is deactivated.
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