Function Frost Protection Valve; Function Pressure Switch - Kärcher HDS 9/50 De Tr1 Service Manual

9.14.2 Function frost protection valve

9.14.3 Function pressure switch

1 Casing
2 Valve
3 Spring
If pressure is applied to the casing (1) during operation of
the pump, the valve (2) closes and no flow is possible.
In low pressure operation the spring (3) pushes onto the
valve (2) so that the gate of the valve is opened. As a re-
sult, water flows through the overflow valve back to the
float container. In the frost protection mode water is
flushed this way and Glysantin is filled in.
Upon starting work (until pressure has built-up) water also
flows from the valve into the return line, which has a posi-
tive effect for the bleeding of the pump.
NOTE
If the valve is defective, the maximum pump pressure is no
longer reached. In this case, the valve must be renewed.
1 Casing
2 Piston
3 Spring
4 Tappet
5 Diaphragm
If pressure is applied to the casing (1) during operation of
the pump, the piston (2) is pressed against the spring (3)
and pushes the tappet (4) onto the membrane (5). This
way, the pressure switch is operated.
In work brakes the spring (3) pushes back the piston (2) so
that the tappet is moved down and releases the pressure
switch.
ATTENTION
Risk of property damage! If water or moisture should leak
from the component, it must be replaced entirely.
Replacing the O-rings only does not provide a remedy in
the long run.
English 5.906-736.0 Rev. 00 (07/15)
57