Compressor Suction Temperature
Compressor Suction Temperature
(OP)
Hello All
So I had a scenario where I was required to select a roof top packaged air conditioning unit, 100% recirculation with the entering air at 86F (mining operation). Needed a capacity of 177 MBH and leaving air of 55F. I could get close, but not quite. The suction temperature was at 50F by default, I lowered it down to 46 and I hit my desired conditions right on. I understand that for each suction temp., there is only one corresponding delta_T you can have.
My question would be how exactly is the correct suction temp. achieved and/or maintained? Or, is it simply a factor dictated by the operational conditions of the condenser-evaporator system? Is this something you can have adjusted to match desired performance?
Just hoping for some insight into this modification I made, if it is correct and what are the effects. I am using a selection software that shows the equipment ratings.
So I had a scenario where I was required to select a roof top packaged air conditioning unit, 100% recirculation with the entering air at 86F (mining operation). Needed a capacity of 177 MBH and leaving air of 55F. I could get close, but not quite. The suction temperature was at 50F by default, I lowered it down to 46 and I hit my desired conditions right on. I understand that for each suction temp., there is only one corresponding delta_T you can have.
My question would be how exactly is the correct suction temp. achieved and/or maintained? Or, is it simply a factor dictated by the operational conditions of the condenser-evaporator system? Is this something you can have adjusted to match desired performance?
Just hoping for some insight into this modification I made, if it is correct and what are the effects. I am using a selection software that shows the equipment ratings.





RE: Compressor Suction Temperature
RE: Compressor Suction Temperature
RE: Compressor Suction Temperature
RE: Compressor Suction Temperature
These two statements contradict each other. By definition, a packaged air conditioning unit has a condenser and compressor included.
RE: Compressor Suction Temperature
RE: Compressor Suction Temperature
Improving liquid subcooling to the TXV may or may not net a reduction in suction temp, but it will improve net refrigeration effect (NRE).
RE: Compressor Suction Temperature
RE: Compressor Suction Temperature
So, when you decreased the suction temperature in the selection program what you did was to tell the program that you were planning to choose a compressor/condenser unit accordingly.
It's not clear what selection program you are using, but we'll guess that it dealt with the evaporator only.
So next you need to pick a compressor/condenser unit with 177 MBH capacity at 46F suction temperature.
RE: Compressor Suction Temperature
RE: Compressor Suction Temperature
The selection program for the evaporator most certainly has air-side factors too.
The suction temperature is only one of several factors that determine the coil's air-side capacity.
RE: Compressor Suction Temperature
RE: Compressor Suction Temperature