Evaporator fan power Calculation

[kalused1]

I am actually calculating the total heat load on a freezers room and dont want to guess the heat load by fans. Can someone help me with the tip I will use to calculate the Heat load by evaporator fans in KW. I need to know how to determine the power requirement of the evaporator fans I will need during design. Is there any table where I can read pressure drops?

 

[houseman20]

If the fan is in the airstream, the heat transfer is equal to net power. So 7.5 kw fan, gives 7.5 kw heat

English units: 10 bhp x 2545 = 25,450 btu/hr

 

[marcoh]

Plus you need to take into account motor efficiency. If the fan shaft power is 7.5kW, assuming direct drive for an evaporator fan (ie not belt losses), and the the fan is 90% efficient, the total heat rejection into the system will be 7.5/0.9=8.33kW

 

[mauricestoker]

Might also depend on type of motor. If heat gain is an issue, you may want to go with ECM instead of PSC.

http://www.engineeringtoolbox.com/electrical-motors-heat-gain-d_707.html