Danfoss 90 Series Service Manual

2. The table shows the acceptable pump charge pressure range for some charge relief valve settings.
These pressures assume 1500 min¯¹ (rpm) and a reservoir temperature of 50°C [120°F], and are
referenced to case pressure.
Charge pressure relief valve
Charge pressure gauge port M3
K90
Adjusting screw
K10
Lock nut
Case drain port L1
52 N•m [39 lbf•ft]
G
B
t
G
B
t
0 - 10 bar [0 - 100 psi]
1 1/16-12
115 N•m [85 lbf•ft]
0 - 50 bar [0 - 1000 psi]
9/16-18
23 N•m [17 lbf•ft]
P106 162E
See appropriate table
M4
M5
Listed pressures assume a pump speed of 1500 min
-1
(rpm). At higher pump input speeds (with
higher charge flows) the charge pressure will rise over the rated setting.
Charge pressure ranges
Model code Measured charge pressure*
20 18.1 – 21.7 bar
[262 –315 psi]
24 22.0 – 26.9 bar
[319 – 390 psi]
28 25.8 – 30.7 bar
[37.4 – 44.5 psi]
* This is the actual charge pressure port gauge reading minus the case pressure port gauge reading.
3. Earlier production Series 90 pumps have a shim adjustable charge pressure relief valve. Shim kits are
available from Danfoss. Remove the plug using a 1in hex wrench and exchange shims behind the
spring to adjust charge pressure. Torque plug to 68 N•m [50 lbf•ft].
4. Later production Series 90 pumps have an external screw-adjustable charge pressure relief valve.
Loosen locknut (K10) and turn the adjusting screw (K90) using a screwdriver or 1/2 in. hex wrench to
adjust charge pressure setting.
Lock nut wrench size
Frame size Wrench size
030 – 100 1-1/16 inch
130 – 250 1-5/8 inch
5. Clockwise rotation of the plug increases the setting and counterclockwise rotation decreases the
setting (at a rate of approximately 3.9 bar [50 psi] per turn). Torque lock nut to 52 N•m [39 lbf•ft].
Service Manual
Series 90 Pumps
Adjustments
520L0818 • Rev 0101 • August 2015 29

Danfoss 90 Series Specifications

General

Brand	Danfoss
Model	90 Series
Category	Water Pump
Language	English