Verify the inputs
Measure or document each input. If a value is only an estimate, record its source and test a conservative alternative.
Wells & water/ CALCULATOR
Pressure-tank nominal size from required drawdown
Estimate the nominal bladder-tank volume needed to provide a chosen usable drawdown between switch pressures.
FROM ESTIMATE TO ACTION
Use the result, not just the number.
Keep the calculation traceable
Save the input link or copied result together with the date, units and assumptions. A number without its inputs cannot be checked later.
Confirm the decision
Compare the estimate with the related guide, current product data and requirements that apply at your location before buying or building.
Inputs to verify
- Required usable drawdown (L)
- Set from the pump minimum run-time and the intended cycling limit.
- Air precharge, gauge pressure (bar)
- Measure only with pump power off and water pressure fully relieved.
- Pump cut-in pressure (bar)
- Pressure at which the switch starts the pump.
- Pump cut-out pressure (bar)
- Pressure at which the switch stops the pump.