how to calculate wattage for tank heaters 2

[wpr]

I need to keep a 1000 gallon outdoor concrete tank from freezing down to 0 degrees F. I see most immersion heaters provide a KW rating but I don't know how to determin the power I need. thanks

 

[Zapster]

Calculate the heat loss. Heat input needs to equal the heat loss at design conditions.

 

[quark]

http://www.chromalox.com/technical/technicalinformation/default.asp

http://www.shuhart.com/web/technical_information.htm#top

These two links will give you simple procedures to calculate the wattage.

 

[chicopee]

Presumably, you can calculate the heat loss from the tank in terms of btu/hr or calories/hr then apply the conversion factors to determin Watts or Kilowatt which should be the rating of the electric heater. Dont forget to apply a fudge factor to your final value.