Grundfos SQ Series - User Manual

Questions and Answers

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Amy FrancoJul 28, 2025
Why Grundfos SQ Water Pump is not working?
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  Tyler WilliamsJul 28, 2025
  Several issues can prevent your Grundfos Water Pump from running. It could be due to blown fuses, which you should replace, checking the electrical installation and drop cable if they blow again. The GFI circuit breaker might have tripped, so try resetting it. There might be no electricity supply, in which case you should contact your electricity provider. Overload can cause the motor protection to cut off the electricity, so check for any motor or pump blockage. A defective drop cable can also be the cause, requiring repair or replacement of the pump/cable. Finally, overvoltage could be the issue, so check the electricity supply.
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lopezjulieAug 4, 2025
What to do if Grundfos SQ runs but no water comes out?
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  tina43Aug 4, 2025
  If your Grundfos Water Pump is running but not delivering water, consider these possibilities: the discharge valve might be closed, so open it. The water level in the well could be too low, requiring you to increase the pump's installation depth, throttle the pump, or replace it with a smaller capacity model. The check valve might be stuck, necessitating you to pull the pump and clean or replace the valve. Alternatively, the suction strainer could be clogged, requiring you to pull the pump and clean the strainer. In some cases, the pump itself may be defective, so repair or replace it.
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Kelly RamirezNov 11, 2025
How to fix frequent start and stop of Grundfos Water Pump?
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  Morgan CruzNov 11, 2025
  Frequent starts and stops of your Grundfos Water Pump can be caused by several factors. The differential of the pressure switch between the start and stop pressures might be too small; increase the differential, ensuring the stop pressure doesn't exceed the pressure tank's operating pressure and the start pressure is high enough for sufficient water supply. Incorrectly installed water level electrodes or level switches in the reservoir could be the issue; adjust the intervals of the electrodes/level switches to ensure suitable time between the cutting-in and cutting-out of the pump. A leaking or half-open check valve can also cause this; pull the pump and clean or replace the check valve. Unstable supply voltage can also cause this issue; check the electricity supply. Lastly, the motor tem...
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Kimberly MedinaNov 18, 2025
Why Grundfos SQ runs at reduced capacity?
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  Abigail SmithNov 18, 2025
  A Grundfos Water Pump running at reduced capacity can stem from several causes: The drawdown might be larger than anticipated, requiring you to increase the installation depth of the pump, throttle the pump, or replace it with a smaller capacity model. Partially closed or blocked valves in the discharge pipe could be the issue; check, clean, or replace the valves as needed. The discharge pipe might be partly choked by impurities; clean or replace the discharge pipe. A blocked check valve can also cause this; pull the pump and clean or replace the valve. The pump and riser pipe may be partly choked by impurities; pull the pump, check, and clean or replace the pump if necessary, and clean the pipes. A hole in the discharge pipe could be the cause; check and repair the piping. The riser pipe ...

Summary

Technical Specifications

Pump Preparation and Setup

Positional Requirements

Guidelines on allowed and disallowed installation positions.

Liquid Temperature and Cooling

Electrical Connection and Safety

General Electrical Guidelines

Installation Guide

General Installation Precautions

Pump and Motor Assembly

Cable Handling and Protection

Fitting cable plugs, guards, sizing, and submersible cable connection.

Pipework and Borehole Installation

Start-up and Operation Settings

Minimum Flow Rate and Pressure Settings

How to start the pump and set up pressure and flow parameters.

Pressure Overload Prevention

Motor Protection and Maintenance

Troubleshooting Common Issues

Fault Finding Chart

Guides for diagnosing and resolving pump problems like no run, no water, or reduced capacity.

Power Supply Verification

Grundfos SQ Series Specifications

General

Motor	Permanent magnet motor
Material	Stainless steel
Maximum Sand Content	50 g/m³
Protection Class	IP68
Type	Submersible Pump
Power Supply	Single-phase or Three-phase
Installation	Submersible
Pump Diameter	76 mm
Frequency	50 Hz or 60 Hz