super heat of blast freezer

[beeran]

Hello dears,

I have a question about the super heat of blast freezers. Assume the room temperature reach on -40⁰c the evaporator temperature should be -46⁰c.to maintain superheat around 6K, the suction line temperature should be -40⁰c. I read some catalogs states that the suction line temp should maintain 16 to 20^0cc.so too much confusion..how to maintain superheat?i don’t know my question is brainless or blunder..Can anybody hit my head?

your beeran​

[mad fridgie]

no more than 10K superheat at the comp inlet

[beeran]

no more than 10K superheat at the comp inlet

thanks mad.then you mean suction line temp will be -36c.

[mad fridgie]

thanks mad.then you mean suction line temp will be -36c.

yes.

Most compressor on LT applications have this limit.

Unless you have liquid injection.

[Magoo]

Hi Beeran.
What is the SST at compressor and actual suction vapour temps at compressor.
Most evap manufacturers state performance based on a TD., ie air on versus SST at evaporator. With air on at -40'C and SST at -46'C is a system TD at 6KTD, suction vapour leaving evap should be in region of -42'C .. example of 2KTD suction loses the compressor SST would be -48'C and suction super heat maxed at 10 KTD vapour entering compressor at -38'C .