If your Danfoss Series 90 piston pump stops running, there are several steps you can take to troubleshoot and possibly resolve the problem. Here are some actions you can consider: Check power supply: Make sure the power supply to the pump is working properly. Check the power supply, electrical connections, and any associated circuit breakers or fuses. Make sure the pump has power. Check Hydraulic Fluid Level: Verify that there is sufficient hydraulic fluid in the reservoir. A low fluid level can cause the pump to stall or run erratically. If necessary, add liquid to the appropriate level as recommended by the manufacturer. Check hydraulic lines and connections: Check hydraulic lines, hoses, and fittings for any leaks, blockages, or loose connections. Leaks or blockages can disrupt the flow of hydraulic oil and affect pump performance. Repair or replace any damaged parts as necessary, and make sure all connections are secure. Check for cavitation: Cavitation can occur when the fluid supply to the pump is insufficient or when the suction pressure is too high. It can cause the pump to stop or make unusual noises. Check for signs of cavitation, such as air bubbles in the fluid, and resolve any problems with the fluid supply, suction line, or inlet filter. Check the filter: A clogged or dirty filter can restrict the flow of hydraulic oil and cause pump failure. Check the filters in the system and clean or replace if necessary. Proper filtration is critical to maintaining pump performance and life. Evaluate System Pressure: Verify that the system pressure is within the pump's specified range. Pressure that is too high or too low will cause the pump to stop. Check pressure gauges, relief valves, and other pressure control components to make sure they are working properly. 90L100-KA-5-NN-80-R-3-S1-E-03-GBA-35-35-24 90L100KA5NN80R3S1E03GBA353524 90-L-100-KA-5-NN-80-R-3-S1-E-03-GBA-35-35-24 90L100KA5NN80R3S1E03GBA353524 90L100-KA-5-NN-80-R-4-C7-E-03-GBA-29-29-26-F023 90L100KA5NN80R4C7E03GBA292926F023 90-L-100-KA-5-NN-80-R-4-C7-E-03-GBA-29-29-26-F023 90L100KA5NN80R4C7E03GBA292926F023 90L100-KA-5-NN-80-R-4-C7-E-03-GBA-35-35-24 90L100KA5NN80R4C7E03GBA353524 90-L-100-KA-5-NN-80-R-4-C7-E-03-GBA-35-35-24 90L100KA5NN80R4C7E03GBA353524 90L100-KA-5-NN-80-R-4-C7-F-03-GBA-26-26-26 90L100KA5NN80R4C7F03GBA262626 90-L-100-KA-5-NN-80-R-4-C7-F-03-GBA-26-26-26 90L100KA5NN80R4C7F03GBA262626 90L100-KA-5-NN-80-R-4-C7-F-03-GBA-26-26-30-F068 90L100KA5NN80R4C7F03GBA262630F068 90-L-100-KA-5-NN-80-R-4-C7-F-03-GBA-26-26-30-F068 90L100KA5NN80R4C7F03GBA262630F068 Review Operating Conditions: Consider any recent changes in operating conditions that may affect pump performance. Factors such as temperature, load, and duty cycle can affect pump operation. Make sure the pump is sized and designed for the application. Consult technical documentation: Please refer to the technical documentation of the Danfoss 90 series piston pump, such as the user manual or troubleshooting guide. The manufacturer's documentation may provide specific directions for diagnosing and resolving common problems. If you have performed the above steps and still cannot solve the problem, it is recommended to contact Danfoss Technical Support or consult a qualified technician with expertise in hydraulic systems. They can provide further guidance and assistance in troubleshooting and solving specific problems with Danfoss Series 90 piston pumps. Check Motor/Pump Rotation: Verify the direction of rotation of the motor driving the pump. Incorrect rotation will prevent the pump from running. Make sure the motor is turning in the correct direction as indicated by the manufacturer's specifications. If the rotation is incorrect, adjust the motor wiring or configuration accordingly. Check the control system: If your Danfoss 90 series piston pump is equipped with a control system, such as an electronic control or a proportional valve, check the system for any malfunctions or errors. Check for error codes, alerts, or indicators that might provide information about the problem. Troubleshoot the control system according to the manufacturer's instructions or consult a technician with specific control system expertise. Check for Mechanical Issues: Check the pump for any mechanical issues or malfunctions. This could include problems with the plunger, valve plate, seals or bearings. Look for any signs of damage, wear or irregularities. If a mechanical problem is detected, it may be necessary to disassemble the pump and repair it or seek the assistance of a qualified technician. Consult Technical Support: If you have performed the troubleshooting steps and are still unable to identify or solve the problem, it is recommended to contact Danfoss Technical Support or contact a certified service center. They have the expertise and skills to provide further assistance and guidance based on your specific model and configuration of Danfoss Series 90 piston pumps. Remember to always put safety first when working with hydraulic systems. When dealing with complex issues or tasks beyond your expertise, follow proper lockout/tagout procedures, wear appropriate personal protective equipment, and consult a professional. 90L100-KA-5-NN-80-R-4-C7-F-03-GBA-26-32-26 90L100KA5NN80R4C7F03GBA263226 90-L-100-KA-5-NN-80-R-4-C7-F-03-GBA-26-32-26 90L100KA5NN80R4C7F03GBA263226 90L100-KA-5-NN-80-R-4-C7-F-03-GBA-29-29-30-F068 90L100KA5NN80R4C7F03GBA292930F068 90-L-100-KA-5-NN-80-R-4-C7-F-03-GBA-29-29-30-F068 90L100KA5NN80R4C7F03GBA292930F068 90L100-KA-5-NN-80-R-4-C7-F-03-GBA-32-32-30 90L100KA5NN80R4C7F03GBA323230 90-L-100-KA-5-NN-80-R-4-C7-F-03-GBA-32-32-30 90L100KA5NN80R4C7F03GBA323230 90-L-100-KA-5-NN-80-R-4-F1-E-03-GBA-35-35-24 90L100KA5NN80R4F1E03GBA353524 90-L-100-KA-5-NN-80-R-4-F1-E-03-GBA-36-36-24 90L100KA5NN80R4F1E03GBA363624 90L100-KA-5-NN-80-R-4-F1-F-03-GBA-35-35-24 90L100KA5NN80R4F1F03GBA353524 90-L-100-KA-5-NN-80-R-4-F1-F-03-GBA-35-35-24 90L100KA5NN80R4F1F03GBA353524 certainly! If your Danfoss Series 90 piston pump stops operating, there are a few more steps to consider: Check and Clean the Suction Strainer: The suction strainer or strainer located at the pump inlet can become clogged with debris or contamination, restricting the flow of hydraulic oil. Check the filter and clean or replace if necessary. Make sure the filter is installed correctly and not damaged. Check for air in the system: Air trapped in the hydraulic system can interfere with the operation of the pump. Bleed the system to remove any air pockets. Follow the manufacturer's instructions on how to properly vent the system, which may involve loosening the vent valve or circulation pump to expel air. Assess the condition of the pump: If none of the steps above resolve the problem, the pump itself may be faulty or in need of repair. Contact Danfoss Technical Support or a qualified technician to assess the condition of the pump and determine whether repair or replacement is required. Document Symptoms and Observations: Throughout the troubleshooting process, document any symptoms, observations, or changes you notice. This information can be valuable when communicating with technical support or service technicians, as it provides a clearer picture of the problem and aids in the diagnosis and resolution process. Preventive maintenance: Once you have resolved a problem with your Danfoss piston pump, consider implementing a preventive maintenance program. Perform regular inspections and maintenance on the pump, following the recommended maintenance intervals, to address any minor issues promptly before larger problems arise. Remember that if you are unsure or not comfortable with performing any troubleshooting steps or repairs, it is best to seek assistance from a qualified technician or Danfoss authorized service centre. They have the expertise and specialized tools to diagnose and resolve complex piston pump problems.