Author Topic: Frigiking BudsBenz Installation  (Read 1690 times)

rbouch8828

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Frigiking BudsBenz Installation
« on: June 10, 2020, 00:05:48 »
A couple of years ago BudsBenz redid my old Frigiking unit and supplied their compressor kit which I installed during the engine bay overhaul.

After that I stripped out the interior and I am finally at the point where I am ready to reinstall the underdash Frigiking unit.

My question is, what is the process for charging up the unit with Freon? Is there anything I have to take into account when making the connection between the Frigiking unit and the drier and compressor lines?

Any advice would be appreciated.

Many thanks!

Roland
RB

doitwright

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Re: Frigiking BudsBenz Installation
« Reply #1 on: June 10, 2020, 01:06:52 »
Since it is likely that your evaporator core in the old Frigiking was last used with R-12 (also known by the brand name Freon), R-12 compressors used a different oil than today’s R-134a compressors. Therefore, if it were mine, I would get the evaporator flushed out and dried with nitrogen. Flushing products can be acquired at the local auto parts store. There are also numerous YouTube videos that go through the process.
Frank Koronkiewicz
Willowbrook, Illinois

1970 280SL Originally Light Ivory - Now Anthracite Gray Metallic

rbouch8828

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Re: Frigiking BudsBenz Installation
« Reply #2 on: June 10, 2020, 12:51:08 »
Thank you for that advice!
RB

rbouch8828

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Re: Frigiking BudsBenz Installation
« Reply #3 on: June 10, 2020, 13:02:04 »
Since it is likely that your evaporator core in the old Frigiking was last used with R-12 (also known by the brand name Freon), R-12 compressors used a different oil than today’s R-134a compressors. Therefore, if it were mine, I would get the evaporator flushed out and dried with nitrogen. Flushing products can be acquired at the local auto parts store. There are also numerous YouTube videos that go through the process.

I just spoke with Vicki at BudsBenz and she told me that the Evaporator was flushed before they sent it back to me, so I do not need to flush it. She also said that the compressor side was filled with freon before they sent it.
RB

badali

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Re: Frigiking BudsBenz Installation
« Reply #4 on: June 10, 2020, 13:57:14 »
It would be best to take it to an AC capable shop and have them vacuum the system down and check for leaks then recharge the system.  If you had any part of the system open change the dryer just before vacuuming the system down.
Brad

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rbouch8828

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Re: Frigiking BudsBenz Installation
« Reply #5 on: June 10, 2020, 14:28:24 »
It would be best to take it to an AC capable shop and have them vacuum the system down and check for leaks then recharge the system.  If you had any part of the system open change the dryer just before vacuuming the system down.

OK, will do.
Thanks
RB

doitwright

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Re: Frigiking BudsBenz Installation
« Reply #6 on: June 10, 2020, 14:38:47 »
Just to be clear. Freon is a brand name and is associated with R-12. Refrigerant is the term associated with R-134a. I have never heard of compressors for automobiles being shipped precharged with refrigerant. Nitrogen perhaps. Condensers and evaporator cores are normally shipped with a nitrogen charge. Compressors are shipped with an oil that is matched with the type of refrigerant to be used in the system. The oil is not compatible with both refrigerants. Say for example, the compressor you have was intended for use with Freon, you would need to get it flushed for use with R-134a. R-12 was replaced with R-134a due to its adverse effects on the ozone layer.
Frank Koronkiewicz
Willowbrook, Illinois

1970 280SL Originally Light Ivory - Now Anthracite Gray Metallic

Shvegel

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Re: Frigiking BudsBenz Installation
« Reply #7 on: June 11, 2020, 00:21:13 »
You need to verify that your expansion valve at the evaporator has been replaced with one calibrated to work with R134a.  I would assume the compressor is oil charged as most are.  Lines are connected then you need to pull a vacuum on the system.  Vacuum is one of the best leak checks as it isn't effected by temperature as using nitrogen or refrigerant is so if the needle doesn't move in a couple hours you are probably OK. 

After you verify there are no leaks the system is filled to the proper level.  This is done by measuring the sub cooling.  After partially charging the system to the point where it will run you check the high side pressure(you will need a gauge set) and then consult a temperature pressure chart(Google R134a Temperature pressure chart)  The chart will give you the temperature of Liquification of the refrigerant.  For example if you had a reading of 120 pounds the refrigerant is liquifying at 98 degrees Fahrenheit.  Sub cooling is the measure of how much cooler the liquid line is where it enters the receiver/drier.  We want about 8 degrees of sub cooling so we want to see 90 degrees at the reciever drier inlet(98 degrees minus 8 degrees of sub cooling.

Do not just charge to a full sight glass on the reciever/drier as R-12 and R-134a do not charge to the same level and the system will be overcharged by about 20 percent.

Or you can bring it to a qualified repair shop.