Results 14 to 26 of 35
08-15-2010, 01:25 PM #14
08-15-2010, 01:48 PM #15
Standing is probably the laymen term.
I'm fairly certain, he used the proper term.
With the possible exception of using the term/phrase saturation pressure.
08-15-2010, 03:03 PM #16
When I use the words "standing pressure," I am indicating more than the fluid being at rest, but also having achieved pressure and temperature equilibrium, usually so that the saturation temperature for that pressure can be compared to the ambient temperature, for determination of the presence of non-condensibles in the system.
"Static pressure" has a familiar and clear meaning, as we saw from some of the responses above.
08-15-2010, 03:09 PM #17
On a hard shut off TXV. "Standing pressure" won't be at equilibrium.
Or a pump down system.
However. While the unit is off, you will still have a static pressure in the lines, condenser, and evap, etc.
08-15-2010, 03:27 PM #18
What determines the static pressure?
I do. That's my job.
08-15-2010, 04:03 PM #19
Pump down systems are usually refrigeration setups, so that would be a unique sector in the industry. I don't think we are dealing with refrigeration in this situation.
Most of the AC systems I see have no trouble equalizing. In fact, many don't use a TXV at all.
I have to agree that if I want to measure "static pressure," it will involve my 510, and not my gauge set.....and I have to admit, this is the first time I have heard someone mention static pressure outside of a discussion of fans and ducts.
08-15-2010, 04:09 PM #20
And what would be the point in knowing this, I wonder? Would the poster state why this is necessary information."The American Republic will endure until the day Congress discovers it can bribe the public with the public's own money.
- Alexis de Toqueville, 1835
08-15-2010, 04:19 PM #21Professional Member
- Join Date
- Jun 2003
As long as the system is physically able to equalize (no hard shutoff TXVs, no solinoids) The system pressure will correspond to the portion of the system that contains liquid and saturated vapor which is usually the coldest point unless the coldest point is already full of liquid.
Imagine the following system:
coil capable of holding 3 LBS in the basement is 70 degrees
Linset capable of holding 2 LBS in the walls is 80 degrees
condenser capable of holding 6 LBS outdoors is 90 degrees
If that system has less that 3 LBS of refrigerant, it should show a pressure that corresponds to 70 degrees.
If it is holding more than 3 but less than 5 LBS it will correspond to 80 degrees
If its holding more than 5 it will correspond to 90 degrees
08-15-2010, 04:24 PM #22
08-15-2010, 04:28 PM #23
08-15-2010, 04:29 PM #24Professional Member
- Join Date
- Jun 2003
08-15-2010, 04:38 PM #25
Your basing your saturation on all the refrigerant being in only X part of the system, if it only has X amount left in it.
Even if it only has 3 pounds in it. There will be some liquid in the condenser, and the line set.
08-15-2010, 04:43 PM #26