General Function Of Series Hde - Ehrle HD 623 Betriebsanleitung

High-Pressure-Cleaning-Systems
1.5.2

General function of series HDE

When the trigger gun (19) is activated, the water from the water system flows
through water inlet (01) in to the boiler container (02) (see also figure 8).
The water in the boiler container (02) is heated by the heating elements (04) to
the adjusted temperature. The desired water temperature may be set from
0 to 80° C via the control element thermostat (03).
The high pressure pump (11) absorbes the water from the boiler container (02)
through the chemical low pressure injector (05) and the temperature limiter (10).
The high pressure pump (11) pressurizes the water to the adjusted operating
pressure.
The temperature limiter (10) is an overheat protection. It switches off the High
Pressure Cleaner when the water temperature exceeds the temperature thres-
hold of 90° C. The device may be switched on again by pushing the reset but-
ton.
The pressure switch (13) monitors the operating pressure and switches off the
high pressure pump (11) after a presetted delay time, when the pressure is be-
low a threshold of 25 bar.
When the trigger gun is activated, the water is pumped through the unloader val-
ve (14) by the high pressure pump (11). This valve is an adjustable control ele-
ment for reducing the operation pressure.
After the non return valve (15), which is integrated in the unloader valve (14),
the pressure gauge (16) indicates the operating pressure. The pressure switch
(17) switches on the High Pressure Cleaner, when the trigger gun (19) is activa-
ted and the pressure is under a threshold of 25 bar.
Depending on the detergent metering valve (07) setting the cleaning detergent
may be admixed to the water from one of the two chemical draw containers (08
or 09). The chemical low pressure injector (05) causes a suction in the cleaning
detergent path, when the high pressure pump (11) is activated and the chemical
metering valve (07) is opened. The resulting underpressure sucks the cleaning
detergent and admixes it through the low pressure injector (05) into the water
circuit.
The adjustment for the cleaning detergent dilution is also accomplished via the
chemical metering valve. When there is no underpressure, the non return valve
(06) separates the cleaning detergent circuit from the water circuit.
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Hochdruck-Reinigungs-Systeme
01 Water inlet 07 Chemical metering valve
02 Boiler container 08 Chemical draw container
03 Thermostat 09 Chemical draw container
04 Heating elements 10 Temperature limiter
05 Chemical low 11 High pressure pump
pressure injector 12 Pump motor
06 Non return valve 13 Pressure switch
Figure 8 High Pressure Cleaner series HDE, functional diagram
Z-0-00007.DWG
14 Unloader valve
15 Non return valve
(integrated in 14)
16 Pressure gauge
17 Pressure switch
18 High pressure outlet
19 Trigger gun
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