Electric heaters are rated in watts for there heating out put.
X number of watts uses's X number of amps of electricity which = X number of BTU's of heat output.
If you buy a $300.00 heater or a $25.00 dollar heater and both heater use the same watts you will get the same amount of heat.
Make sure that you are very careful that you don't over load the TT wiring or the power cord to the trailer as this can be a fire hazard.
Determining How Many Btu You Need
1
Measure the length and width of your room using a tape measure.
2
Find the square footage of the space you plan to heat with your electric heater by multiplying length times width.
3
Multiply the square footage of the room by the estimated 10 watts of electric heat required to heat each square foot. For example, a 12- by 12-foot room measures 144 square feet. Multiplying this by 10 reveals that a 1,440-watt heater is required to heat the space.
4
Calculate Btu by multiplying the number of watts by 3.41. A 1,440-watt heater generates 4,910 Btu per hour.
$25.00 works for me!
Hope this helps Tim