Hello.
I'm a new member here. I recently got my first job as a chemichal engineering in a factory with french fries. There is a problem though with the freezer that cools the fried potatoes. The system uses liquid ammonia, and the problem description is that we can't cool the potatoes enough. I have a few questions, and i'd be more than happy if someone could enlighten me into this matters.
First of all i have a simple (i guess) question. The compressor displays the suction pressure in units of -40°C/R. Why is that? I can't figure out the math between the units of pressure that equals °C/R.

What else should i look at in order to understand the source of the problem? If ammonia leaves the freezer in order to go to the compressor at -40 degrees, it seems that there ins't a problem with the flow of ammonia or the comporessor system. In the freezer there is a big fan, circulating the air, and there is also the coil that if filled (?) with ammonia.
How can i find out if the coil is fully filled with ammonia? If the temperature of the suction in the compressor is -40, i should have temperature in the coil at least -40 degrees celcius. Am i right? Does anyone have any guidelines, or ideas about what things to check?