Recharging Refrigeration

[babylonlarry]

I have a Technautics holding plate engine driven R 134 system. It used to have aeroclip connectors with check valves to prevent coolant from leaking when replacing driers, and also has them at other connection points I believe. One was bad at a service call a few years ago and I found another one,between the condensor and the drier, to hang up when I had problems about a year ago and removed the guts (check valve). I replaced the drier and charged with about one and a half 12 ounce cans of R 134. It ran great for a year. I recently had a failure to cool and decided to replace the drier and recharge starting with a small oil (2 oz oil and 2 oz R 134), then adding 134 til the sight glass showed only an occasional bubble.

I added 1 & 3/4 cans of R134 and had frost quickly develop on the low side where it comes to the compressor. I have a thermometer on the holding plate and have noticed the following: Last charge when there was no frost on the low side, it would cool to 7 degress F in about 45 minutes of fast idle and get down to 4 or 5 in another 15 minutes. Now, It seems to stop at 10 to 12 degrees and I am thinking it may be overcharged with R 134.

QUESTION: Can I simply bleed off a bit of coolant on the high side port? If so should I do it when running or stopped? TIA for any guidance here, Larry

[redbopeep]

Originally Posted by babylonlarry

QUESTION: Can I simply bleed off a bit of coolant on the high side port? If so should I do it when running or stopped? TIA for any guidance here, Larry

one is not supposed to release 134 to the atmosphere. I've heard AC techs say that you can release (via a hose) into water and not violate EPA regulations.

Do you know the pressures you're supposed to have (high and low side) ? If so, the wise thing to do would be to go ahead and invest in the pressure gage system for refrigeration/AC systems. We have one which we've used for the car and the house AC systems to check charge levels and wouldn't mess around w/o the gages unless absolutely necessary.

Best regards and good luck with your project.