Kranzle 1152TST Operation Manual page 23

The pressure gauge shows full pressure although the trigger
gun with safety catch has been closed. The motor constantly swit-
ches on and off.
Possible cause no. 2: The non-return valve is soiled or defective.
There is no guarantee if the pump is damaged by
defective O-rings due to air induction or lack of water
(cavitation).
Proceeding:
Switch off the HP cleaner and pull plug
from socket. Stop water supply. Unscrew
pump outlet.
Take out check ball and check for soiling
or damage.
Also check stainless steel seat of ball
inside the pump housing for soiling or
damage.
If sealing rings are defective replace
O-rings at once.
23