1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Heater - Heat Exchange Questions:

  1. Oct 11, 2011 #1
    I recently acquired a few things that I'm hoping I can use to build a heater for a small area (10'H x 12'W x 12'L).

    Things I current have:

    1. 20 gallons of used motor oil.
    2. An old 5200 BTU window AC unit. The blower components work, the coils are 'supposedly' good, but the compressor is bad.
    3. A design for an oil burner + boiler

    I've got a few problems that I need some help solving:

    1. I want the blower discharge air temp to be 125 degrees F. That obviously means my boiler water temp must be higher--but how much higher (145-165 F?). How would I calculate the ideal water temp so that I can get the temp I want to come out of the system?

    2. Assuming I don't need a water circulating pump, how can I then calculate the boiler water flow rate at the water temp solved for in Q1 (above)? If I do need a water circulating pump, how would I calculate the ideal water flow rate to achieve my desired output temp?

    3. How would I calculate the ideal capacity of my boiler tank so that it contains enough heat to maintain a continuous heating for at least 45 minutes?

    4. How would I then calculate the heat transfer rate between the boiler tank & the combustion chamber?

    Thanks in advance for any help that you can provide.


    - The AC evaporator coil uses 1/8" diameter copper tubing
    - The dimensions of the evap coil are: 7"H x 13"W
  2. jcsd
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook

Can you offer guidance or do you also need help?
Draft saved Draft deleted