Question regarding evaporator/condenser designs
Question regarding evaporator/condenser designs
(OP)
1.superheat
Psig Saturated Temp Suction line temp superheat temp.
58 32 44 12
64 37 47 10
70 41 50 9
can some1 help me understand the ratings above..
Saturated temperature is easy ok.
Suction line temperature is the temperature before or after the evaporator? my guess is after the evaporator..
As for the superheat temperature: they say it defines the liquid content of R-22 in the system at the exit of the evaporator, but i dont understand the principle..plz help with this.
2. Does anyone know a good program for coil design? i'm using a program called evap-cond but we just dont seem to get along very well.
3. Any good books or references?
4. About the compressor to be chosen for refrigeration application. i'm finding that their is a conception that if u need to transfer 10 tons of cooling to a room, u choose a compressor that is rated at 10 tons. but shouldn't a smaller one do?
Thank you guys
Psig Saturated Temp Suction line temp superheat temp.
58 32 44 12
64 37 47 10
70 41 50 9
can some1 help me understand the ratings above..
Saturated temperature is easy ok.
Suction line temperature is the temperature before or after the evaporator? my guess is after the evaporator..
As for the superheat temperature: they say it defines the liquid content of R-22 in the system at the exit of the evaporator, but i dont understand the principle..plz help with this.
2. Does anyone know a good program for coil design? i'm using a program called evap-cond but we just dont seem to get along very well.
3. Any good books or references?
4. About the compressor to be chosen for refrigeration application. i'm finding that their is a conception that if u need to transfer 10 tons of cooling to a room, u choose a compressor that is rated at 10 tons. but shouldn't a smaller one do?
Thank you guys
Elie Abou Jaoudeh





RE: Question regarding evaporator/condenser designs
As far as compressor selection, the tonnage of the compressor is going to be determined by the design load and the specific volume of the suction gas your trying to move. In general terms this is based on suction pressure and the pounds per minute you need to circulate to meet design load. The horsepower is determined by the pounds per minute of refigerant you need to circulate and the heat of compression. I'm sure someone will go into further detail but in simple terms that about covers it.
I'm stating it pretty simply here. ASHREA has some good materials when it comes to system sizing.
I'm not a real engineer, but I play one on T.V.
A.J. Gest, York Int./JCI
RE: Question regarding evaporator/condenser designs
I'm not a real engineer, but I play one on T.V.
A.J. Gest, York Int./JCI
RE: Question regarding evaporator/condenser designs
As for the compressors i have a brochure for a certain line of compressors, but they don't give the mass flow rate of anything else, they just give max. suction pressure, and Tons of heat..the selection is being done according to that tonnage ! my question is because i always designed using mass flow rate !!
Elie Abou Jaoudeh
RE: Question regarding evaporator/condenser designs
I'm not sure I fully understand where your confusion lies.
On the second note it sounds like the manufacterer has saved you the some of the calculations for finding the required displacement. When they state the max. operating pressure, they are saying at this suction/discharge pressure they guarrenty xyz tons. It sounds like it might be possible to oversize the compressor using max. tonnage delivered.
I'm not a real engineer, but I play one on T.V.
A.J. Gest, York Int./JCI
RE: Question regarding evaporator/condenser designs
Saturation temperature = 32 for 58psig
while the superheat temp = 12 !!!!
what does that mean, and how can i find it for a system without physiscal measurement
Elie Abou Jaoudeh
RE: Question regarding evaporator/condenser designs
I'm not a real engineer, but I play one on T.V.
A.J. Gest, York Int./JCI
RE: Question regarding evaporator/condenser designs
Elie Abou Jaoudeh