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Circulators, Heaters

Water Heating Time Calculations
The specific heat of water is 4.186 J/g°C
The equation for calculating the needed energy value for a certain water heating process is:
Q=c*m*(dT)
cspecific heat (J/g°K) of the heated liquid
m the mass of the liquid that needs to be heated (g)
dT temperature difference during the process (°K)
Q needed amount of energy for the process (J)
For example: In order to heat up 200L of water from 45°C to 90°C, we'll use the equation
above:
Q = 4.186 J/g K *200,000g * 45K = 37,674,000J
Conversion of the energy (Q) to power (P): 1 Watt=1 J/s
Thus, in order to calculate the time needed for the process (given a heating element of
2000W power) :
t(s)=Q/P
time=37,674,000J/2000(J/s)=18,837s=313.95min=5.23h=05:14:00
Meaning, it takes about 5 hours to heat up 200L of water from 45°C to 90°C with 2000W
heating power.
A few examples of the time needed to heat up various volumes of water in different
powers:
Assumptions: Optimal contiditions, no heat is lost to the environment, full conversion of the
heating element's voltage into heat.
If we were to increase the power twice the heating time will shorten in half for the same
volume, and so on.
immersion Heaters

