In this video
- Explains why you'd pump down a mini split: moving the unit or repairing the indoor head, restoring it to how it shipped from the factory
- Remove the service valve caps using a 3/16-inch Allen (hex) wrench
- Connect low-side gauges to the larger suction line, then close the liquid line (the smaller tube) first
- Watch the gauge fall toward zero, then close the second valve to trap all the refrigerant in the outdoor unit
- No vacuum pump or recovery machine needed; the compressor does the work, and the whole process takes less than 30 seconds
Questions this video answers
How do I recover refrigerant back into the outdoor unit on a mini split?
Hook your low-side gauges to the larger suction line, close the liquid line valve first with an Allen wrench, and watch the gauge drop toward zero. Once it reads near zero or shows a slight vacuum, close the suction line valve too. All the refrigerant is now stored back in the outdoor unit.
What size Allen wrench do I need to close mini split service valves?
A 3/16-inch Allen (hex) wrench fits the service valves on most mini split outdoor units and is what you'll use to close both the liquid and suction lines during a pump down.
Do I need a vacuum pump or recovery machine to pump down a mini split?
No. The mini split's own compressor pulls the refrigerant back into the outdoor unit; you only need your gauges and the correct hex wrench to close the valves.
Which valve do I close first when pumping down a mini split?
Close the liquid line valve first, which is the smaller of the two copper lines. Watch the gauge on the larger suction line drop toward zero before closing that second valve.
How do I know when all the refrigerant is back in the outdoor unit?
Watch the low-side gauge after closing the liquid line. When it reads down to zero, or shows just a slight vacuum, all the refrigerant has been pulled back into the outdoor unit and you can close the second valve.
Why would I need to pump down a mini split's refrigerant?
You'd pump down the system if you're moving the unit or making a repair to the indoor head. It restores the refrigerant to the outdoor unit the same way it shipped from the factory, so the indoor lines can be safely disconnected.
How long does a mini split pump-down procedure take?
Once your gauges are connected and you have the correct hex wrench, the whole process of closing both valves and moving the refrigerant back into the outdoor unit takes less than 30 seconds.
Transcript
Read the full transcript
Hi guys, this is Dave. I'm behind the camera, and Todd's in front of the camera today. He's going to show us how to move refrigerant and store it in the outside unit of the mini split. The unit's up and running right now, and it's all going to be basically restored to factory settings by getting the refrigerant back to the outside unit, because that's the way it ships. So Todd, take it away.
Okay, you have service valve caps here that you need to remove, and you will need a 3/16-inch Allen wrench. Then you will need your gauges, just the low side, hooked up onto the larger of the two copper lines, which is the low side. The first thing to do is close the refrigerant on the liquid line, the smaller of the tubes, and put the Allen wrench into the larger one as soon as you're done, because it's only a matter of seconds to get the refrigerant restored into the outdoor unit.
Let me show the gauge here. Okay, once you get this one closed, you'll see the gauge moving down. That outer ring is really hard to read, but it was at around 100 and now it's getting down. When it gets down to zero, or just below it, that's when you want to close the other valve.
All right, so now both valves are closed. You look at the gauge, and it's actually got a little bit of a vacuum on the refrigerant lining into our unit, so you know all the refrigerant is in the outdoor unit.
Okay, so it's just that easy, huh? It's that simple. Okay, thanks, appreciate it.
