What you will see
- Less water reaching the tank during the same operating period.
- Flow changing through the day.
- A controller warning or repeated stopping.
- Reduced delivery after pipework or bore conditions change.
Why it happens
Grundfos’s solar-pump sizing guidance considers water demand, static lift and dynamic water level. These hydraulic requirements matter alongside the available power and pump selection.
The service team should compare actual conditions with the design and investigate possible hydraulic, mechanical and electrical causes. A change in water level or delivery route can alter the duty even when the pump and panels are unchanged.
Use comparable observations. The time taken to fill a tank is only meaningful if the tank level, other water use and test conditions are known. Avoid running a pump deliberately under an abnormal condition to obtain a measurement.
What the pump has to overcome
Compare tank fill times only under similar conditions.
What you can check yourself
- Record the pump and controller models from documents.
- Note the approximate delivery change and when it occurs.
- Save controller warnings and normal display readings.
- Identify recent pipework, tank or bore-service changes.
- Provide the original design flow and lift information if available. Do not enter a well, climb a tank or open electrical equipment to gather missing details.
What not to do
- Do not bypass dry-run protection, change drive parameters or repeatedly restart a pump that faults. Do not add PV modules before the controller and pump arrangement are reviewed.
When to call us
- Request a joint electrical and pump-system assessment for persistent low flow, repeated stopping or a sudden unexplained change.
Tubewells around Faisalabad and Lahore
Farm and tubewell pumps around Faisalabad and Lahore are affected by falling water levels. Send our team flow observations and design records.
Send us
Equipment models, design records, flow observations, alarms, recent changes, and your city and area.
Technical references
Reviewed 25 September 2026. Manufacturer documents are cited for general principles; your exact model’s manual always applies.