I know of "2" units that have been running like this for 2 seasons..,no call backs.Tech did say he had trouble getting his Delta T. in spec. No customer complaints! I,ve wondered myself,what long term affects may be?
Back in one of the OP's posts, he said he would "run the vac pump for an hour," or something to that effect.
OP: the time is not the benchmark to use. A micron gauge IS the way to ensure you have pulled a proper vacuum.
We have left the age of running the pump for "awhile" behind us. Auto mechanics used to run a vac for only 30 mins in the days or R12 systems. I went to a class once where this was stated as the correct method.
You can get an inexpensive micron gauge for less than a c-note.
Do it right.
[Avatar photo from a Florida training accident. Everyone walked away.]
2 Tim 3:16-17
RSES CMS, HVAC Electrical Specialist
AOP Forum Rules:
I'm going to theorize about what would happen in this system.
Originally Posted by Cosmicmuffin
Let's say his pressures were right for the system, but it was mixed with nitrogen/r22 refrigerant:
1. The compressor would pump a nitrogen, r22 vapor mixture through the condenser
2. R22 loses heat and condenses to a liquid, nitrogen remains a vapor in the liquid line
3. Now you have liquid refrigerant mixed with nitrogen vapor bubbles.
4. As these bubbles flow through the metering device, there wouldn't be any metering done until liquid refrigerant enters the metering device.
There's no possible way a system could cool properly. I'm sure your coworkers Delta T was next to 0, and anything he said otherwise was false.
The damage is done I think you should take advantage of your mistake and take readings to see what non condensibles in a system looks like. Then reclaim,change your drier, and run a deep vacuum, weigh in your proper charge. Don't rush that is where accidents happen!
The systems that I've dealt with that have non-condensibles in them did work well enough.
Originally Posted by Thermodynamics
They just tripped on high pressure on occasion.
I was under the impression that nitrogen would find a place to "settle" in the system, such as the top of the condenser coil, any truth in that?
Originally Posted by jpsmith1cm
Depends if metering device has liquid seal or not.