[bfletcher7]

Hi. I may have interest is removing up-to 5 oz of R410 from my system, wondering if it could be overcharged. To save the time of hooking up the recovery machine can I just attach my recovery tank, run the system, and crack the liquid line valve? If so, do I need to concern myself with any loss of oil? Thx

 

[yuri]

If you cool the tank down with ice or in a fridge or freezer and the pressure is lower than the system pressure when not running then it will naturally flow into the tank and you can do it from the low side/suction line w/o losing oil or running it. If you do it quickly from the liquid line then yeah some oil will be lost. How much is anyone's guess. I doubt it would be enough to damage anything but that is just a guess. Oil is constantly flowing around and being trapped and released in the evap etc so I am sure the manufacturers allow for that and it is not critical the amount to an ounce or two.

 

[yuri]

If the recovery tank is completely empty and you pull a 30" vacuum on it with a vacuum pump then the first 6 oz. will rush into it like crazy but I would still cool it down.

 

[bfletcher7]

Yur awesome; thanks. Last year I ran out of nitrogen before getting a refill, so I stored the tank with a little R410. I'll check the tank's pressure first.

 

[yuri]

Yeah when I was in trade school and we still had R12 we bought it in big 100 lb torpedo/propane sized tanks. The instructor had refillable 30 lb tanks (B4 check valves came around). We would have to pull a vacuum and stick the tank into one of our lab walk in coolers and then refill it. Worked real well.

 

[BayouRunner]

Just a suggestion with the 410a I would take it from the liquid side. All the refrigerants that end with an A are to be charged as a liquid because the different components separate as a gas. This is just my theory I could be wrong but in principle I think it would be right. I don't use much 134a but it has happened to me twice where some of the gas has leaked out of the tank the refrigerant didn't operAte properly. Now this was with refrigeration. I am assuming it would be the same in 410a. Would like to here any other thoughts on this.

 

[yuri]

Fractionation/fractionate the refrigerant.

Was talked about in the industry when 410 came out for resi. Concern was that when you lose a few lbs from a normal leak then what blend is left as it leaks as a gas. From what I know with small amounts it is not a problem. However if you lose the charge and top it up several times it may be. 6 oz I would not worry about. Have not heard from Lennox etc that it is a problem. Other types beside 410 may be a bigger problem.

Google refrigerant fractionation for articles.

Beenthere does refrigeration a lot and knows the different refrigerants and may know more.

 

[beenthere]

R134A is a single compound gas. It can be charged and recovered as either a liquid or vapor the same as R12, R502(a near azeotropic blend of R22 and R115), and R22 can/could be.

To the OP, yes its done fairly often.

 

[supers05]

R410A s a*zeotropic, but near-azeotropic blend.

400 series refrigerants are zeotropic. (2 or more components with different boiling properties.)

500 series refrigerants are azeotropic. (2 or more components with identical boiling properties.)

600 series refrigerants are single component natural refrigerants.

For 400+series the capital trailing letter is the specific makeup designation. (what percentages of each component. First come first served type of assignments)

For below 400 series, the lower case trailing letter is the isomer designation. Each isomer is the same chemical formula, but different atomical arrangements This can lead to radically different properties, like stability and efficiency.

All zeotropic refrigerants should be liquid charged (or adjusted). R410A is fairly forgiving though.

Cheers!

 

[bfletcher7]

Now you guys have me worried about something I wrote off a couple years as not being an issue based on what I read in the refrigeration manual. Over a few years my system (a 14 lb charge) has been topped off due to leaks, fully recovered for repairs, and all the while the remaining recovered R410 has been reused. I don't recall the exact content but the manual states that studies have shown that many top offs posed no issue. But let me ask this. When I recover I bring the tank indoors over night and the next day at a known ambient temp I check the temp of the tank and compare it to a PT chart. I've done this to check for non condensables. Would this step also verify whether or not the blend lost its integrity?

 

[yuri]

No as you need to know the molecular makeup/count of different atoms of the blend per given area.

Ie: 2 atoms of X and 3 atoms of Y = perfect blend in a 1 cubic inch area. 2 of each would be wrong.

 

[bfletcher7]

So then, since now I'm talking about more than pulling out a few ounces and worried about the integrity of my refrigerant given the history, if I recover all of it and refill with virgin R-410A it poses two additional questions:

1. Being unlicensed, will I be able to find someone to whom I can take my old refrigerant for disposal?

2. I never worried about oil since I always reused the recovered refrigerant. Can I buy another tank, connect the system to its liquid port and connect that tank's vapor port to the recovery machine input and connect my other recovery tank to the machine's output? Will that place the oil in the first tank, and then do I buy an injector and place an equal amount into my system?

... or how forgiving is R-410A? Because I'm getting a headache, lol.

 

[BayouRunner]

I've only experienced problems with 134a. Haven't had any issues with 410a. First time I weighed a charge in a refrigerator (bottom of the tank) and customer called and said it wasn't working properly. I went back with a fresh drum, weighed my charge and everything was fine. Since I've had trouble twice I apply the same principle to the 410a if I work on it. That's why I was asking for feedback. I think at 5 ounces in a system I wouldn't think you would have any trouble. I was just sharing my experience with the other refrigerant.

 

[yuri]

I have no idea what goes on in the US with refrig recovery and disposal. Nobody other than licensed refrig techs can handle it in Canada. We take it back to the wholesaler and they send it away for re-use/cleaning or destruction if it is contaminated.

 

[BayouRunner]

Same here

 

[beenthere]

No cert needed for R410A in the USA.

 

[bfletcher7]

What, been?

 

[beenthere]

No cert needed for R410A in the USA.

Dang smart phone with auto correct.

 

[bfletcher7]

Thx. Can you advise:

1 How I can locate a resource where I could take contents of a tank for disposal?

2 Offer a little advice as to how I can determine how much oil gets extracted if I perform a complete evac and recharge with virgin?

3 Do you agree that R410A may have lost its integrity during several top-offs/evacuations with no means for me to verify it?

Thanks

 

[beenthere]

Thx. Can you advise:

1 How I can locate a resource where I could take contents of a tank for disposal?

Being a contractor, I have never had to try and find a source as the supply houses will take them back from me. Only thing I can think of, is call the HVCA supply houses around your area.

2 Offer a little advice as to how I can determine how much oil gets extracted if I perform a complete evac and recharge with virgin?

Generally, about four ounce when you recover a system.

3 Do you agree that R410A may have lost its integrity during several top-offs/evacuations with no means for me to verify it?

Thanks

Carrier simulated a leak that lost 50% of the systems charge, and recharged that system. And repeated that simulation and top off 50 times on that test unit. They found no noticeable change in system performance.

R410A has about a .3°F glide. Almost would have had to be doing recovery as a vapor only to change its mix ratio. I've done top offs on the same R410A systems a good number of times. Never had a lost of cooling from doing so. Also have put back in what I took out to fix the leak on some of those systems. No change in cooling ability.

It is possible that some air may have been in your hoses and got into the system. That will effect cooling performance.

Next, if the tank wasn't cleaned as well as it should have been when you got it. It can cause a contamination of the system.