Electric Duct Heater Sizing Calculator

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.

An example of calculating the minimum air velocity needed. Face area h 2 5 w 0 5 144 in2 ft2 12 2 5 24 0 5 144 in2 ft2 1 53 ft2. This hvac calculator is the closest estimate to the actual manual j calculation done by hvac pros. Heater selection sizing determining the size of your duct heater.

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. Answer a few questions about your energy source and garage and the garage heater calculator free tool recommends models that will do the job. 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. This hvac load calculator quickly estimates the size of your heating and cooling system in btu s.

Calculate the duct size by using a duct calculator. First multiply by 133 the total cubic feet of area determined in step 2. When shopping for heaters many people make the mistake of choosing the wrong size for their actual needs. Our free garage heater calculator takes the guesswork out of selecting a garage heater.

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. Multiply that result by the temperature increase you calculated in step 3. Take the guesswork out of garage heater sizing. The result rounded off to the nearest thousand is the total btus or heater size you need.

A one kw heater will produce 3 413 btu s per hour. Enter any two parameters to get the third. Use our heater sizing charts to determine what garage heater is right for you. In the example this would be 40 000 btus.

Cfm btu s δt x 1 08 input. Dividing by 250 the normal wattage per linear foot equals 6 84 feet of baseboard heater required. Rise f δt volts amps. If a room is 250 square feet the result will be a duct size of 8 inch round.

Rounding up this means that 7 feet or 84 inches of heater is needed. Cfm volts x amps x 3 412 δt x 1 08 δt f volts amps. Calculate the btus you need.