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princeJOY
07-02-2013, 09:15 AM
I'm a newbie trying to understand the HVAC system. My query is on what parameter is the evaporator temperature fixed? What would be its value for room air conditioning, chiller, freezer etc? I'm trying to select a electrical compressor for a cooling load of about 0.8 ton.

chillerman2006
07-02-2013, 04:26 PM
general rule of thumb, is your evaporating pressure / saturated temperature is 10k below your required space temperature

R's chillerman

princeJOY
08-02-2013, 05:08 AM
I have a compressor datasheet. Its details are as follows..
10036


My cooling capacity is around 2500 Watts. My required temp is 25deg celsius. To use this compressor, I have to run it with rpm in between 2800 and 3700 rpm. The corresponding evap temp is 10deg celsius. Is this deduction correct or am I looking at a mismatched compressor?

Tesla
08-02-2013, 07:33 AM
Hi princejoy
That is a question different from the first. The compressor is med to hi temp and will do the job at 3700 but struggle towards 2800. So go for a bigger compressor. What rpm will you be using - fixed on voltage supply?
Did you mean you cooling load as opposed to cooling capacity?

princeJOY
11-02-2013, 04:27 AM
What rpm will you be using - fixed on voltage supply?
Did you mean you cooling load as opposed to cooling capacity?
My exact cooling load is around 2813Watts. Based on my understanding, I thought a rpm between 2800 and 3700 for a evaporator temperature of 12deg celsius(last column;mid- last and last before row) would do the job. Is my understanding correct?

princeJOY
11-02-2013, 04:29 AM
I can also run the compressor at any desired speed with a constant voltage supply.(depends on the control circuit modification).