KHD7122 Manual

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In case of a leakage there is no guarantee for possible
consequential damages.
Proceeding:
Check connections from the high-pressure
cleaner to the high-pressure hose and from
the high-pressure hose to the safety trigger
gun and also the connection between lance
and safety trigger gun for tightness.
Switch off the cleaner. Shortly press the
trigger of the trigger gun with safety catch
to decrease the pressure. Remove high-pres-
sure hose, trigger gun with safety catch and
lance and check the O-rings. If the O-rings
are damaged they have to be replaced.
Proceeding:
Switch o the high-pressure cleaner and
pull plug from socket. Stop water supply.
Operate safety trigger gun catch several
times to decrease the pressure.
Unscrew pump outlet.
There is no guarantee if the high-pressure pump is damaged by
defective O-rings due to air induction or lack of water (cavitation).
Remove check body and check O-Ring for
soiling or damage. Also check seal seat in-
side pump housing for soiling or damage.
If sealing rings are defective replace
O-rings at once.
Having closed the safety trigger gun, the
pressure control valve/safety valve must
switch and the stainless steel pressure
gauge must show „0“ bar. Failing to switch
and with the stainless steel pressure gauge
continuously showing full pressure, this
could be due to leakage at the high-pressure
pump, at the pressure switch, at the high-
pressure hose or at the safety trigger gun.
HD 7/122, HD 10/122
Problem
After closing the safety trigger gun, the pressure control valve-safety valve keeps
switching. The stainless steel pressure gauge continuously displays full pressure.
Possible cause No. 1
Leckage.
HD 7/122, HD 10/122
Problem
After closing the safety trigger gun, the pressure control valve-safety valve keeps
switching. The stainless steel pressure gauge continuously displays full pressure.
Possible cause No. 2
The non-return valve is defective.
Small repairs - do it yourself Small repairs - do it yourself