PDA

View Full Version : difference between condenser pressure & condensing pressure







shanbal
08-03-2014, 12:00 PM
Dear all,
I am new in refrigeration. what is the difference between condenser pressure and condensing pressure.
Condensing pressure means Compressor discharge pressure.
I am using Ammonia compressor.Suction pressure indicates -13 Psig (minus 13) and Discharge pressure indicates 184 Psig.
Any one tell the corresponding temperature.

Shanbal.

passandscore
08-03-2014, 02:32 PM
To answer your question you'll need to start by understanding compound gauges and pressure/temperature charts.

Here is some light reading.

1) Video - Understanding Compound Gauges & PT Charts (http://www.youtube.com/watch?v=Hq8h0081Cbw)
The video is a little lame but informative.

2) Using P-T Analysis As A Service Tool (http://www.parker.com/literature/Sporlan/Sporlan%20pdf%20files/Sporlan%20pdf%20Miscellanous/Form%2010-135_52013.pdf)

3) Ammonia PT Chart (http://www.engineeringtoolbox.com/ammonia-pressure-temperature-d_361.html)

Rob White
09-03-2014, 12:47 AM
Dear all,
I am new in refrigeration. what is the difference between condenser pressure and condensing pressure.
Condensing pressure means Compressor discharge pressure.



Words that's all, words

Condensing, condenser, discharge pressure , saturation, all words that
describe a similar thing.

Evaporating, evaporator, boiling, suction pressure, saturation all words that
describe a similar thing.

You need to understand the basics in refrigeration terms and definitions.

The condenser is part of the system where the refrigerant condenses
to a liquid at a certain temperature, that is the condensing or condenser
pressure / temperature. That pressure can be read with a gauge that is fitted
anywhere on the discharge side of the compressor all the way through to the
liquid side of the condenser.

Except for slight differences due to pressure drops (which we don't need to
bother about at this level) the pressure / temperature reading will be the same
at all points in that high side of the system and that pressure / temperature is
only a reflection of what is happening in the condenser.

Inside the condenser, the refrigerant is changing from a vapour to a liquid at the
temperature / pressure shown on the high side gauge.






I am using Ammonia compressor.Suction pressure indicates -13 Psig (minus 13) and Discharge pressure indicates 184 Psig.
Any one tell the corresponding temperature.

Shanbal.


Those numbers don't add up? Gauges read pressures and in refrigeration pressures
indicate what the refrigerant is doing. In the high side the refrigerant is condensing in
the condenser, in the low side the refrigerant is evaporating in the evaporator.

It is all about temperature, but we can't do much with the temperature so we control
the pressure and by controlling the pressure we can control the temperature.

Rob

.

mbc
10-03-2014, 06:25 PM
condenser pressure is a your gauge pressure = ( your condensing pressure at ambient temperature + delta T )

Gary
11-03-2014, 12:53 AM
Start here:

http://www.refrigeration-engineer.com/forums/showthread.php?19701-Refrigeration-101

TF12
12-03-2014, 02:41 AM
Rob,
I agree. If you're just starting out forget about pressures. Think temperature. Remember that all pressures have a corresponding temperature and in order for your condenser to reject heat to the atmosphere the condenser must be at a higher temperature than the ambient. In order to move heat energy out of your product or refrigerated space the evaporator TEMPERATURE must be lower than what your desired product temperature will be to absorb that heat energy.
The greater the difference in temperature the faster the transfer of heat energy.
This is the tip of a giant iceberg
Great industry to be in
Best of luck!!