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.
Electric duct heater sizing calculator.
You can also do this by checking for them online or by using a manual that is sold by distributors.
Dividing by 250 the normal wattage per linear foot equals 6 84 feet of baseboard heater required.
This hvac calculator is the closest estimate to the actual manual j calculation done by hvac pros.
A 25 kw open coil duct heater is to be installed in a duct that is 12 inches high by 24 inches wide.
Heater selection sizing determining the size of your duct heater.
Rise f δt volts amps.
Face area h 2 5 w 0 5 144 in2 ft2 12 2 5 24 0 5 144 in2 ft2 1 53 ft2.
Rounding up this means that 7 feet or 84 inches of heater is needed.
Answer a few questions about your energy source and garage and the garage heater calculator free tool recommends models that will do the job.
First multiply by 133 the total cubic feet of area determined in step 2.
Cfm btu s δt x 1 08 input.
Cfm volts x amps x 3 412 δt x 1 08 δt f volts amps.
Calculate the duct size by using a duct calculator.
The heat load estimate is based on your climate region total square footage number of rooms or zones you want ceiling height insulation type number of windows and doors.
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.
If a room is 250 square feet the result will be a duct size of 8 inch round.
Our free garage heater calculator takes the guesswork out of selecting a garage heater.
A one kw heater will produce 3 413 btu s per hour.
This hvac load calculator quickly estimates the size of your heating and cooling system in btu s.
Enter any two parameters to get the third.
In the example this would be 40 000 btus.
An example of calculating the minimum air velocity needed.
Take the guesswork out of garage heater sizing.
1 electric heat temperature rise method.
When shopping for heaters many people make the mistake of choosing the wrong size for their actual needs.
The result rounded off to the nearest thousand is the total btus or heater size you need.
Use our heater sizing charts to determine what garage heater is right for you.