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theapprentice
11-09-2007, 01:02 AM
hey everyone I need help calcualating how my kw's of refrigeration the new pakage unit I just installed is doing. The tradesman I work with has set it as my home work but I have lost one of my main tafe books and cant find any formulas. Can anyone please help me. All im after is the formula so I can work it out on my own. But we had 19.2 air on the coil 27.7 air off the coil with an air flow rate of 2350L/s. on heating of course. Sorry if this is in the wrong section im a newbie. Thanks for all your help
chris.

Ravi
13-09-2007, 04:36 AM
I have yet to know this forum policy about homework questions. Most of the professional forums on the net either don't allow it or have separate forums. Till the time I know it, here is the formula for you.

Take pains to remember this forever if you continue to be in HVAC. The sensible heat can be calculated by Q = 1.1xcfmxdT, where Q is rate of heat flow in btu/hr, dT is temperature difference in F.

Go and get an excellent and free unit conversion software called Uconeer from www.katmarsoftware.com (http://www.katmarsoftware.com)

Good luck,

ozairman
13-09-2007, 06:14 AM
hey everyone I need help calcualating how my kw's of refrigeration the new pakage unit I just installed is doing. The tradesman I work with has set it as my home work but I have lost one of my main tafe books and cant find any formulas. Can anyone please help me. All im after is the formula so I can work it out on my own. But we had 19.2 air on the coil 27.7 air off the coil with an air flow rate of 2350L/s. on heating of course. Sorry if this is in the wrong section im a newbie. Thanks for all your help
chris.

Watch out as one of your tafe teachers may be lurking here!!
Q=M x C x ∆T
where Q= amount of heat produced
M=mass of air flowing
C= specific heat of air
∆T=delta T or temp difference
google for more info there is lots around.

Go search the secondhand bookshops library for a copy of "Princinples of Refrigeration SI edition" by RJ Dossat it is indispensable.