Danfoss iSave 40 ERD: Recommended Service Intervals

1. General Information

This guideline provides information on the recommended service intervals. The recommendation is based upon good engineering practice and on experience gained from operation even under extreme conditions. The recommendation is for guidance only.

2. Design/Features

Danfoss iSave ERD is designed for long operation and low maintenance and life cycle costs. Provided that the ERD has been running according to the Danfoss specifications, Danfoss guarantees one year service-free operation, however, max. 18 months from date of production. After one year of operation it is recommended to inspect the iSave and replace worn parts, if any.

If the Danfoss recommendations concerning system-design (see our data sheet) are not followed, the service life of the iSave ERD might be affected.

The recommended service intervals on the different parts in the iSave ERD appear from the table below:

3. Service Intervals (Serial no. 01 to 03)

¹⁾ For detailed information on parts, see Service guide AX290231141118en-000101 Parts list

4. Service Intervals (Serial no. 04 and newer)

¹⁾ For detailed information on parts, see Service guide AX290231141118en-000101 Parts list

5. Appendix 1 (Serial no. 01 to 03)

Stator

The stator does not have to be replaced even if there are grooves on the surface.

Figure 1: Visual representation of a stator. Text advises to sand down any burrs on the surface.

Rotor

Measure the height difference between the points indicated in Fig. 2 and Fig. 3.

Figure 2: Depicts a point on the rotor with no normal wear.

Figure 3: Illustrates the most worn side of the rotor, adjacent to the shaft. Wear is confirmed if the height difference exceeds 0.15 mm.

Side plates

Measure the height (thickness) difference between the points indicated in Fig. 4 and Fig. 5.

Figure 4: Shows a point on the side plate exhibiting minimal wear.

Figure 5: Displays the side plate's most worn area. Wear is indicated if the height difference surpasses 0.15 mm.

The surface in contact with the rotor can be restored by lapping with extra-fine sandpaper (ISO P800, CAMI grit 320) on a flat surface. Ensure thorough cleaning of the side plate post-lapping. The minimum allowed thickness for side plates is 10.40 mm. The combined thickness of both side plates in a unit should not be less than 20.85 mm.

Pressure measurement

Leakage and wear of the rotor and side plates can be indirectly assessed by measuring pressure in one of the LP bleed ports of the vane pump. If the pressure in the bleed port is 2 barg (29 psig) higher than the pressure in the LPin port, the vane pump requires examination, and the side plates, possibly the rotor, may need replacement. The bleed port thread is G 1/4" (BSP).

Port plate

Measure the height (thickness) difference between the points indicated in Fig. 6 and Fig. 7.

Figure 6: Illustrates a point on the port plate.

Figure 7: Indicates the measuring point on the port plate where the outside land is most worn, which may differ from the depicted position. Wear is present if the height difference exceeds 0.05 mm.

Restoration is possible by lapping with extra-fine sandpaper (ISO P800, CAMI grit 320) on a flat surface (see Fig. 8). Clean the port plate thoroughly after lapping. Lapping is permissible until the throttling groove reaches a minimum depth of 0.1 mm.

Figure 8: Depicts the process of lapping the port plate.

Valve plate

Wear occurs on the valve plate where it contacts the port plate's land. Valve plates are considered worn when these contact grooves reach a depth of 0.03 mm.

6. Appendix 2

Potential inspections related to disassembly and assembly procedures are under development.