Eng. AG
09-05-2009, 04:47 AM
Hi! I'm Eng. AG and I just signed in. I'm a design engineer at a consultancy firm and I'm fairly new. I wanted to ask help from you guys since you are experts in the field of refrigiration. Here is my question:
How can I compute for the electrical load of a walk in freezer?
Here are the facts about the walk in:
Size: 15m (L) x 7.5m (W) x 4m (H)
Stored products: Meat products, fish, poultry etc.
Storage temperature: -18C to -10C
Lights: 10 units of 2 x 40kW lamps
I've computed for the cooling load using Kent's handbook and turned out to be 3.5 TR. My senior said it's ok (then again, he's not an expert in refrigiration so I'm not really sure) and I've assumed that the compressor would have a 60% efficiency therefore 3.5TR=17kW turns into 21kW. Then I assumed that the compressor consumes about 60% of the electrical load, which makes 40% of the total diverted to fans, system pump etc. which turns 21kW into 35kW.
As it turns out, the electrical engineer wants to crucify me for this value. Obviously I did something wrong and I'm not really sure what it is. Please help me.
Best regards,
Eng. AG
How can I compute for the electrical load of a walk in freezer?
Here are the facts about the walk in:
Size: 15m (L) x 7.5m (W) x 4m (H)
Stored products: Meat products, fish, poultry etc.
Storage temperature: -18C to -10C
Lights: 10 units of 2 x 40kW lamps
I've computed for the cooling load using Kent's handbook and turned out to be 3.5 TR. My senior said it's ok (then again, he's not an expert in refrigiration so I'm not really sure) and I've assumed that the compressor would have a 60% efficiency therefore 3.5TR=17kW turns into 21kW. Then I assumed that the compressor consumes about 60% of the electrical load, which makes 40% of the total diverted to fans, system pump etc. which turns 21kW into 35kW.
As it turns out, the electrical engineer wants to crucify me for this value. Obviously I did something wrong and I'm not really sure what it is. Please help me.
Best regards,
Eng. AG