Heating/ CALCULATOR
Heating buffer tank volume
Estimate the water volume needed to absorb surplus heat for a chosen minimum heat-source run time.
Use the delivered heat output at the operating condition, not electrical input or fuel rating.
Use the heat accepted by the smallest zone or operating condition that causes cycling.
Confirm the appropriate minimum run time and cycling limit with the equipment manufacturer.
Use only the temperature range that the heat source, controls and emitters can actually use.
Include only connected water that participates during the short cycle.
Heat that must enter storage
8.0 kW
Heat stored during target run
2.7 kWh
Required participating water volume
229 L
Estimated additional buffer volume
149 L
Run time supported by existing water
7.0 min
Water is treated as 1 kg/L with specific heat 4.186 kJ/(kg·K). Heat-source output, active load and temperature swing are constant, and all stated water participates uniformly. Tank stratification, pipe and tank loss, control deadband, defrost, minimum flow, hydraulic separation and manufacturer minimum-volume rules are excluded. Final selection must follow equipment and safety requirements.