AC,
I received my gauges and vacuum pump yesterday and when I got them I realized that I had ordered a different set than what I had thought (I must have looked at 50 different sets last Sunday night when I placed the order and somewhere along the line I went into "cyber space unconscious mode" and for some reason thought I went with the "do all gauges) anyway the set I "really" ordered goes to 500-PSI HS and 250-PSI LS so it worked out, they look nice and seem to work well
It was a package deal on ebay $60 free shipping for gauges and pump, I'm sure you know what that means, yes it is a HF pneumatic powered venturi style pump. After doing some research on that pump I found a lot of people reported 28" hg and for just a few extra bucks I thought why not, I also thought since im here on the gulf coast and ambient outside temps are mid 90's or higher that the moisture would boil out even it didn't quite get down to 28"hg.
I got home from work around 3:30 so I had plenty of time to "get things started" I had to bring everything down the street to a friends house who has a nice 80 gallon high output compressor as well as a new bottle of refrigerant
I had gotten everything set up and ready to pull my first vacuum and within about 2 minutes sure enough the gauge was reading 28"hg so I let it run for the recommended 10 minutes and closed the valve turned of the pump started up my stopwatch app on my phone and let it set for 15 minutes, after 15 minutes the gauge was now reading 27"hg so I turned the vacuum on again and after a few times of doing this I could tell if it was due to a leak or if the gauges were just "settling" I checked all the connection and tightened the connections a bit and still the same results. I decided it was good enough and proceeded with my first charge, the only other test equipment I grabbed was my favorite pistol style infrared temp gauge and my KILL A WATT meter, also were we set it up outside was out of reach of the water hose to simulate the ground loop so I submersed the condensing coil in about a 2 gallon container and monitored the water temp, I followed your charging instruction carefully and within a mater of minutes I had a nice frost forming right at the end of the cap tube and all the way down into the evaporator coil, as I watched the gauges and slowly gave it shots of gas into the LS I finally got it up to 70-PSI but the HS was reading 250-PSI I let it run under these conditions for about 15 minutes and as the water temp rose so did the wattage so i flushed it constantly using a 5 gallon bucket with fresh water and making a mess
but it worked.
The bad news is when I brought it back home after it seemed to be working and set it up outside on the back porch to play with it some more (this time with a water hose to simulate the ground source loop) it was working great and ran it for a good 45 minutes, now I had my other 2 temp gauges which I used to monitor out coming air temp (40 degrees F on high fan speed) and water temp. I was too tired at this point to set up the sub-cooling and super-heat testing but just by touch I would say it was about a 20 degree difference. The bad news is this morning after leaving the gauges on it all night, the pressure dropped about 100-PSI and when I turned it on it was still working but the LS stabilized @ 25-PSI and HS 150-PSI, I guess the leak could be in the gauges but I will definitely be do some leak testing today.
I will take pictures of today's work and testing and post sometime tonight, I'm on my way out the door to go play some Paintball its the only sport I play and it keeps me in shape.
Thank You All!
JRoode32