Face area h 2 5 w 0 5 144 in2 ft2 12 2 5 24 0 5 144 in2 ft2 1 53 ft2.
Electric duct heater sizing calculator.
Our free garage heater calculator takes the guesswork out of selecting a garage heater.
Cfm btu s δt x 1 08 input.
Rise f δt volts amps.
Rounding up this means that 7 feet or 84 inches of heater is needed.
In the example this would be 40 000 btus.
A 25 kw open coil duct heater is to be installed in a duct that is 12 inches high by 24 inches wide.
Multiply that result by the temperature increase you calculated in step 3.
This hvac calculator is the closest estimate to the actual manual j calculation done by hvac pros.
Given all the different options available for heaters space vented gas console and more narrowing down the choices can be a great way to ensure that you are choosing the best option.
Calculate the btus you need.
Heater selection sizing determining the size of your duct heater.
Cfm volts x amps x 3 412 δt x 1 08 δt f volts amps.
The result rounded off to the nearest thousand is the total btus or heater size you need.
If a room is 250 square feet the result will be a duct size of 8 inch round.
Enter any two parameters to get the third.
If you know the cfm of your air handler and the temperature rise needed you can use the chart below to approximate the kilowatt rating of the duct heater needed for your application.
This hvac load calculator quickly estimates the size of your heating and cooling system in btu s.
Standard heaters are not available in this length so in this case a single 8 foot or two 4 foot heaters would be the likely choice.
You can also do this by checking for them online or by using a manual that is sold by distributors.
Use our heater sizing charts to determine what garage heater is right for you.
Calculate the duct size by using a duct calculator.
A one kw heater will produce 3 413 btu s per hour.
First multiply by 133 the total cubic feet of area determined in step 2.
1 electric heat temperature rise method.
Take the guesswork out of garage heater sizing.
An example of calculating the minimum air velocity needed.
When shopping for heaters many people make the mistake of choosing the wrong size for their actual needs.
