Heat loss calculation tool.

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bagabum

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[font=Tahoma, Verdana, Arial, sans-serif]FYI. I used the below [/font][font=Tahoma, Verdana, Arial, sans-serif]tool to determine [/font][font=Tahoma, Verdana, Arial, sans-serif] heat transfer for calculating insulation requirements of my new build[/font][font=Tahoma, Verdana, Arial, sans-serif].  The post build test: I placed[/font][font=Tahoma, Verdana, Arial, sans-serif] an electric [/font][font=Tahoma, Verdana, Arial, sans-serif]heater that was 415 watts in my new DIY camper and determined through t[/font][font=Tahoma, Verdana, Arial, sans-serif]he [/font][font=Tahoma, Verdana, Arial, sans-serif] tool that the combination of my known ([/font][font=Tahoma, Verdana, Arial, sans-serif]surface[/font][font=Tahoma, Verdana, Arial, sans-serif] area, [/font][font=Tahoma, Verdana, Arial, sans-serif] R[/font][font=Tahoma, Verdana, Arial, sans-serif]-Factor, [/font][font=Tahoma, Verdana, Arial, sans-serif]  heater BTU [/font][font=Tahoma, Verdana, Arial, sans-serif]and outside temp[/font][font=Tahoma, Verdana, Arial, sans-serif]erature) [/font][font=Tahoma, Verdana, Arial, sans-serif] should level out at around[/font][font=Tahoma, Verdana, Arial, sans-serif] 55 deg F  with 17 deg F ambient (calculated), it actually levele[/font][font=Tahoma, Verdana, Arial, sans-serif]d out at[/font][font=Tahoma, Verdana, Arial, sans-serif] [/font][font=Tahoma, Verdana, Arial, sans-serif]53[/font][font=Tahoma, Verdana, Arial, sans-serif] deg F  (actual) allowing several hours for everything to stabilize[/font][font=Tahoma, Verdana, Arial, sans-serif].  I generated a composite R-[/font][font=Tahoma, Verdana, Arial, sans-serif]factor by combining R-factors for wall and floor [/font][font=Tahoma, Verdana, Arial, sans-serif]panels, windows, door material and[/font][font=Tahoma, Verdana, Arial, sans-serif] studs, all by the [/font][font=Tahoma, Verdana, Arial, sans-serif]ratio [/font][font=Tahoma, Verdana, Arial, sans-serif] of [/font][font=Tahoma, Verdana, Arial, sans-serif]surface areas and R-factors for each. [/font][font=Tahoma, Verdana, Arial, sans-serif]Belie[/font][font=Tahoma, Verdana, Arial, sans-serif]ve it or not, pine [/font][font=Tahoma, Verdana, Arial, sans-serif]studs are 40% of your[/font][font=Tahoma, Verdana, Arial, sans-serif] losses on 2" foam walls, I use 10% of total surface area for 16" centers. Maybe you can use this to calculate your heating or cooling requirements Vs trial and error. This listed [/font][font=Tahoma, Verdana, Arial, sans-serif]address is the tool:  [/font][font=Tahoma, Verdana, Arial, sans-serif]https://rimstar.org/renewnrg/heat_transfer_loss_calculations.htm[/font][/SIZE]
 
Sorry but that sounds way too technical for me. I just leave 1 foot sticking out front under the covers and guess what the temperature is.;););).
 
Since studs wouldn't be holding together your vehicle, trailer or whatever, they don't need to be 16" on center. Depending on the build, you might not even need studs.

Also, our mobile living quarters tend to have more stuff per cubic foot than sticks & bricks dwellings. That mass tends to hold the prevailing temperature -- cold or warm -- longer than air.
 
nature lover said:
Sorry but that sounds way too technical for me. I just leave 1 foot sticking out front under the covers and guess what the temperature is.;););).
Yes, I agree with you, that  is a much better method ...thanks
 
MrNoodly said:
Since studs wouldn't be holding together your vehicle, trailer or whatever, they don't need to be 16" on center. Depending on the build, you might not even need studs.

Also, our mobile living quarters tend to have more stuff per cubic foot than sticks & bricks dwellings. That mass tends to hold the prevailing temperature -- cold or warm -- longer than air.
Yes, agree with you, let stuff heat your build...thanks
 
[font=Tahoma, Verdana, Arial, sans-serif][size=small]It sounds like your thinking it through but [/size][/font][font=Tahoma, Verdana, Arial, sans-serif][size=small]I can't imagine 415 watts [/size][/font][font=Tahoma, Verdana, Arial, sans-serif][size=small]giving you much heat but it will use a lot of battery/solar power if your not plugged in. Even with 400 watts of battery bank and solar that's going to drain your power supply in a very shot time. [/size][/font]




[font=Tahoma, Verdana, Arial, sans-serif][font=Tahoma, Verdana, Arial, sans-serif][size=small][size=small]https://www.quora.com/How-much-solar-power-do-I-need-to-run-a-heater?share=1[/size][/font][/font][/size]
 
Cousin_Eddie, the 415 W elec heater was for testing purposes. Wanted to make sure actual heat loss of walls is known.  I am making my own heater concept. I do not want propane, diesel, wood burning, generator  or battery heating on my new build (a 6x12 box that slides into an aluminum utility trailer). I have a lot of unused solar energy during the day that I want to save for night use heating so I needed to know how much temp rise I would get from 1400 Btu so I could make a nomogram.. My plan was to get 1500 Btu for 8 hrs from my heater which is  enough for 20 deg F weather...thank you  for constructive  input.
 
Yeah but you have not calculated in the solar gain effect oof the sdun hitting the walls on some days but not on others. Calculate all you want but yoy will sstill be too hot in mid sdummer asnd need to use shade cloth or reflective matrrials. In. Winter the floor will be too cold .
 
maki2 said:
Yeah but you have not calculated in the solar gain effect oof the sdun hitting the walls on some days but not on others. Calculate all you want but yoy will sstill be too hot in mid sdummer asnd need to use shade cloth or reflective matrrials. In. Winter the floor will be too cold .
Wrong, wrong and wrong..  thanks for your input
 
I am wondering how your heating system worked out. Have you built it and tested it yet?

Unlike some other people, I appreciate your use of a heat loss calculation tool. For any custom system to work, it has to provide the real world thermal flux needed by the space to be heated. Calculating the size of heating system needed for your insulated space is step one, since there is no purpose to proceeding with a build if the proposed system cannot meet the calculated level of demand.
 
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