CHARGE PRESSURE
RELIEF VALVE REMOVAL
1. Clean pump externally with clean solvent to
remove debris.
2. Using a 24mm wrench, remove the charge
pressure relief valve. (V010)
1. Lubricate the external O-ring (V024) using
petroleum jelly.
2. Install the new charge pressure relief valve.
Using a 24mm socket, torque to 47-57 N•m
[35-42 lbf•ft]
CHARGE PRESSURE
RELIEF VALVE
INSTALLATION
CHARGE PRESSURE
RELIEF VALVE
ADJUSTMENT
1. Install a 50 bar [1000 psi] pressure gage in charge pressure gauge port M3 (next to the adjust-
ment screw). Install a 10 bar [100 psi] gauge at one of the case drain pressure ports L1, L2,
L3, or L4. Operate the system with the pump in neutral (zero displacement) when measuring
charge pressure.
2. The table shows the acceptable pump charge pressure range for some nominal charge relief
valve settings (refer to the model code located on the serial number plate). These pressures
assume 1800 pump rpm and a reservoir temperature of 50°C (120°F), and are referenced to
case pressure.
3. Adjust valve. Clockwise rotation of the adjusting screw increases the setting, and counter-
clockwise rotation decreases the setting (at a rate of approximately 2.7 bar [39 psi] per turn).
4. Torque locknut to 36-44 N•m [26-33 lbf•ft] using a 19mm socket.
5. When desired cha
rge pressure is achieved, remove the gauges and plug the ports.
Charge pressure ranges
Model code Measured charge pressure*
20 bar [290 psi] ± 1.5 bar [21.8 psi]
24 bar [348 psi] ± 1.5 bar [21.8 psi]
26 bar [377 psi] ± 1.5 bar [21.8 psi]
30 bar [345 psi] ± 1.5 bar [21.8 psi]
* This is the actual charge pressure port
gauge reading minus the case pressure
port gauge reading. Factory set at 1800
min
-1
(rpm) with a reservoir temperature
of 50° C (120° F)
Listed pressures assume a
pump speed of 1800 rpm. At
higher pump speeds (with
higher charge flows) the
charge pressure will rise over
the rated settings.
V024
V010
47-57 N•m
24mm
36-44 N•m
[26-33 lbf•ft]
19mm
Locknut
6mm
Adjusting screw
Charge pressure gauge port M3
0 - 50 bar [0 - 1000 psi]
1/4 inch
20-27 N•m [15-20 lbf•ft]
Case drain port L2
0 - 10 bar [0 - 100 psi]
9/16 inch
96-136 N•m [70-100 lbf•ft]
© Danfoss, 2013
11139819 • Rev AB • September 2013
1
Service Kit Instructions
H1 pump charge pressure relief valve
Replacement procedure
