ucUnitCloudInternational unit matrix

Use case

Heating, plumbing and flow rate

Keep volumetric flow, pressure and temperature difference separate so that datasheets do not lead to wrong conclusions.

Working steps

  1. Note the flow unit used in the datasheet: m³/h, l/min or l/s.
  2. Bring all values into a common unit before comparing them.
  3. For pump and fitting data also check whether US or imperial gallons are meant.
  4. Do not read volumetric flow as a power figure: temperature difference and heat capacity are missing for that.
  5. For pressure figures clarify whether absolute pressure or gauge pressure relative to the atmosphere is meant.

Checks

Unit family: Flow rate

Matching conversions

Cubic metre per hour to Litre per minutem³/h → l/minFlow rateLitre per minute to Cubic metre per hourl/min → m³/hFlow rateLitre per second to Litre per minutel/s → l/minFlow rateUS gallon per minute to Litre per minuteUS gal/min → l/minFlow rateCubic metre per hour to Cubic foot per minutem³/h → ft³/minFlow rate

Further reading

TableFlow rate: m³/h, l/min and l/sGuideFlow rate in heating and plumbing

Sources

BIPM SI BrochureSI base units, prefixes and official SI context.NIST Guide to SI Appendix BNIST conversion-factor method and non-SI factors.
When not to use

Do not use as the sole basis for official, medical, safety-critical or contractual decisions.

Citation

Citation note: UnitCloud, use case, sources reviewed: September 2026. Source basis: BIPM SI Brochure · NIST Guide to SI Appendix B.