Heating

Heat output

Output

8,00kW

Flow

467l/h

Temperature drop

15,0K

Heat output links heating power, mass flow and the temperature drop. The calculation uses the specific heat and density of water. Given two of the three values, the missing one is found.

Output

8,00

kW

Flow rate

467

l/h

Temperature drop
15,0K
Mass flow
459kg/h

Find

Save in —

How it's calculated

Heat output links power, volume flow and the temperature drop. The relation is Q = m · cp · ΔT, with the specific heat and density of water at the mean temperature. Two of the three values give the third. Mass flow is volume flow times density. Mean temperatures from 0 to 110 °C are allowed, and the temperature drop must be above zero.

Worked example

500 l/h, a drop of 15 K, mean temperature 60 °C: output 8.57 kW, mass flow 492 kg/h.

FAQ

Why not simply 1.16 times litres times kelvin?
The factor 1.16 is an approximation near 10 °C. Here cp and density are taken at the mean temperature.
May the temperature drop be zero?
No. Without a temperature difference there is no output. An empty or negative drop is not treated as zero.
Does this cover brine or glycol?
No. The properties are those of water. Mixtures need a different density and specific heat.
Is pressure drop included?
No. This calculator is only the heat balance. Pipe friction is in heating pipes and in pressure drop.