I just ran a recovery and only got 142g from a unit that should have 1100g charge. Unit was OFF during recovery, done to fix a leak somewhere. I stopped the recovery BEFORE it reached 0 PSI to avoid pulling air into the tank from the leak. I was expecting maybe half (5-600g) because when we stopped using it, it was still blowing just a little cold air...not much though. Did I not get all the refrigerant out? I only have 1 service port, on the low (suction) side. I did remove the shrader with a VCRT. Any help would be great. My concern is when I fix the leak and recharge with the proper weight, could I overfill it and damage it, if there is a good amount left in it. Are you supposed to run the machine during recovery in order to circulate the refrigerant to the service port in order to pull it out...then at a certain PSI stop the mini split before damaging anything?
Mini-split recovery to tank, should it be running or no?
- Thread starter jfharper
- Start date
fitter30
Well-known member
You can pull the system into a slight vacuum. The refrigerant will be coming out of the oil. If you want or 1 lb of pressure. Since refrigerant is about 4 times heavier than air i aways purge the reclaim tank ( vapor) in case there's any. Short burst.
Sorry, I'm not understanding...maybe I used the wrong terminology. I was pulling all the refrigerant out of the mini split to fix a leak and I only got 142g (after TARING the recovery tank), was expecting more, did I leave a bunch of refrigerant in the mini split? My understanding is you remove all R410A from mini split, close service valves, fix leak in lineset, test with nitrogen pressure, pull a vac, then weigh in proper R410A after reopening service valves.
danski0224
Well-known member
Did you use a recovery machine?
Generally speaking, it is not good practice to use the compressor to recover refrigerant and pull the system into anything resembling a vacuum.
Some equipment has valves in the circuit that traps refrigerant. You might need to reference the service manual for your equipment.
Generally speaking, it is not good practice to use the compressor to recover refrigerant and pull the system into anything resembling a vacuum.
Some equipment has valves in the circuit that traps refrigerant. You might need to reference the service manual for your equipment.
American Locomotive
Well-known member
I believe some minisplits have a dedicated recovery mode that opens up any electronic expansion valves. But if you think of where the service port is on a minisplit, you should be able to get all of the gas out.
Not getting much luck with the service manual. fitter30 mentioned I may have gas trapped between a check valve and the 3-way valve restricting the recovery machine from pulling out all the refrigerant. He mentioned closing one of the valves (I'm going to try the low valve) and running the unit in heat then cool for a brief time to see if that frees up the gas from the check valve indicated by a pressure rise. If it does, I'll try the recovery machine with the split OFF and see if I get the refrigerant out. I hope this method releases all the refrigerant I need to remove, so when I weigh back in the refrigerant, I don't overfill because I didn't get it all out to begin with.
justinjoyal
Well-known member
You can close the service valves after recovering so contaminants don’t get in there, but you should open them before pulling a vacuum and weighing in the charge.
Also, did you purge the recovery machine after you recovered the refrigerant? It usually holds a few ounces of refrigerant once it stops, at least mine does. I gotta put it in self-purge mode to squeeze out whatever’s left in it.
Yes, but I'm stuck at the first step...remove all the R410A...I only got like 142g. The unit holds 1100g or 2.4lbs. The stain on the concrete is only about 4 inches in diameter...I can't see that stain being 2.2lbs of refrigerant...unless the R410A released as a gas. The service port was wet and sticky/oily and concrete showed a stain. Is there any way to confirm you got all the R410A out of the unit?
Yes, I did purge the recovery machine after recovery.
Yes, I did purge the recovery machine after recovery.
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purplezr2
Well-known member
Refrigerant is a gas.....
Oil is added to the system to lubricate the parts(Pump). More than likely you are seeing oil the drained out of the system.
OK, thanks...so is there any pressure evidence by running the machine briefly to see if the unit has any R410A in it? My concern is, if I try to refill after fixing the leak, and weigh in 2.4 lbs and it already had some in it, I could overfill it and ruin it.
danski0224
Well-known member
I wouldn't operate the equipment.
Running it under a vacuum will damage/destroy the compressor and non-condesibles (i.e.: not refrigerant) can damage other stuff.
There are magnets that go on solenoid stems to open them, if you think refrigerant is trapped there.
Running it under a vacuum will damage/destroy the compressor and non-condesibles (i.e.: not refrigerant) can damage other stuff.
There are magnets that go on solenoid stems to open them, if you think refrigerant is trapped there.
Thanks. As soon as it wasn't adequately cooling inside anymore, we stopped operating it. Running under a vacuum...that was my understanding too. I only ran it for about half a minute in cooling mode at a vacuum to see if it would pressurize before I turned it off. Before that, I cannot confirm it wasn't running under a vacuum because I did not put a gauge on it until now. I was just trying to determine if it still had any coolant in the system after I tried using the recovery machine and only getting 142g. Another guy told me if I have a stain on the concrete I probably ran almost all the coolant out of it. So, maybe I should just proceed with fixing the line leak, N2 test, after which open the two valves, run a vacuum on the entire system open, then weigh in the 1100g specified for the full charge.
American Locomotive
Well-known member
What brand and model unit is this? If you look up the manual, there is usually a "service mode".
Since minisplits have a variable speed compressor, they can run quite low on refrigerant before their performance really starts to drop - especially if you do not need the full capacity.
Since minisplits have a variable speed compressor, they can run quite low on refrigerant before their performance really starts to drop - especially if you do not need the full capacity.
justinjoyal
Well-known member
If you can’t recover any more, briefly release the spring valve, you’ll quickly see if there is remaining pressure or just a tiny bit left over vapor… no big deal.
86turbodsl
Well-known member
NOT running! It will evac whole system from a single schraeder.
EG4 Hybrid Solar 12K non-plug-n-cool version. I'll look again, all I have is the install manual, I don't remember seeing service mode.
Thanks, I'll try to figure where the spring valve is.
Thank you...good to know.
I can't find anything online about a spring valve on a mini split...is it called something else, or can you guide me as to where it might be and how I might release it?
danski0224
Well-known member
Best guess is that spring valve = Schrader.
Thanks...if that's at the service port, I used a VCRT to get that out of the way.
justinjoyal
Well-known member
Yeah, spring valve = schrader. It’s a French Canadian expression, I let that one slip out.
When you are done recovering, just shut the valves at your gauges/machine and slightly untighten the hose at the service port and you’ll see if there is remaining pressure or not, no big deal.
No worries...help offered transcends language/culture...I appreciate it.
I remember trying to determine what an olive was, given from an UK perspective, until I found the answer being a brass compression sleeve.
Just thought of another question...since I saw a stain on the concrete, about 4 inch in diameter under the king valve, someone mentioned that being oil...after I fix all this, is it at all prudent to attempt adding oil back in to the system somehow?
OK, one more thought, is it possible to do a triple evac on a mini-split with R410A? So, after leak repair, N2 pressure/bubble test, both kings open, vacuum entire system to max vacuum (evac #1). R410A upside down into service port (schrader removed) using KwikCharge to about 0 PSI. CLOSE low side king, vacuum again hoping open high king will pull R410A through...at -30mmHG open low side king and vac to max acheivable (evac #2). Repeat (last sentence) (evac #3). Is this possible or make sense to do? After which weigh in factory charge.
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justinjoyal
Well-known member
That’s not how triple evac works.
Also, you don’t measure vacuum in mmHg.
I don’t mean to be rude, but I am wondering if you have the knowledge to (properly) work on that mini.
Also, you don’t measure vacuum in mmHg.
I don’t mean to be rude, but I am wondering if you have the knowledge to (properly) work on that mini.
Right, I know people use N2, but it seems better to use R410A, or whatever refrigerant your unit takes...understanding how the triple evac works, meaning you are flushing the system 3 times of moisture, air, etc, pushing the flush through the system the two times you inject R410A. I was wondering if on a mini split it could work like this...given they only have one port to work with, not 2 ports like regular A/C unit on either side of the system circuit.
danski0224
Well-known member
Refrigerant needs to be reclaimed, and it's expensive.
But, you do you.
But, you do you.