Author Topic: ask for approach temp and space temp  (Read 642 times)

Offline teeckg

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ask for approach temp and space temp
« on: June 10, 2019, 12:55:39 PM »
I have one point don't sure.
the question gives Sapce temp=15, Approach temp 5, what is the air leaving temp?
   15-5=10 ?     or leaving temp=space temp=15 ?

Offline Admin

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Re: ask for approach temp and space temp
« Reply #1 on: June 10, 2019, 06:46:43 PM »
I was taught the approach temperature is the difference between your liquid line temperature and the outdoor ambient temperature.  For example if the liquid line temperature was 90°F and the outdoor temperature was 85°F the approach temperature would be 5°F.

I attached pictures below from a Lennox installation manual that explain how to use the approach method.

I’m not sure how knowing the indoor ambient and approach temperature could help you solve the air leaving coil temperature.  In fact you should not use the approach method if the indoor ambient is not between 21°C and 26°C.  Your questions says the indoor ambient is 15°C, which is too cold.