How to clean out dessicant beads from system

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Noquacks
Posts: 12
Joined: Thu Jun 29, 2017 2:18 pm

How to clean out dessicant beads from system

Postby Noquacks » Sun Jul 16, 2017 9:01 am

People,

Civic 2001 EX, system was not cooling right (blew cold air sometimes, blew ambient other times). Pressure in low side was zero while high side was 170 or so. Something was clogging the valve, I figured. Dismantled the exp valve and noticed small 2mm beads of what has to be dessicant stuffed/jammed into the lower (smaller) orfice in the exp valve. Also visible from inside cab looking into the lower line (high psi line/narrow one) beads were collecting there as well.

So, how do dessicant beads get in there? Also, now these beads have to be spread out everywhere, right? How to flush out? Suction line had no beads visible, do I assume there are none there?

Do I blow out the condenser too or just buy new?

Thanks.
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Cusser
Posts: 221
Joined: Sun Apr 24, 2016 6:29 am

Re: How to clean out dessicant beads from system

Postby Cusser » Sun Jul 16, 2017 9:15 am

Noquacks wrote:Civic 2001 EX, system was not cooling right (blew cold air sometimes, blew ambient other times). Pressure in low side was zero while high side was 170 or so. Something was clogging the valve, I figured. Dismantled the exp valve and noticed small 2mm beads of what has to be dessicant stuffed/jammed into the lower (smaller) orfice in the exp valve. Also visible from inside cab looking into the lower line (high psi line/narrow one) beads were collecting there as well.

So, how do dessicant beads get in there? Also, now these beads have to be spread out everywhere, right? How to flush out? Suction line had no beads visible, do I assume there are none there?

Do I blow out the condenser too or just buy new?


The desiccant (I spelled it correctly) beads are normally held inside a porous bag in the receiver-drier. Yours has broken somehow. I suspect that the beads are only in the receiver drier, the high pressure line(s) leading from there to the expansion valve, and the expansion valve itself. I'd suggest new drier, new expansion valve, and to backflush that high pressure line with solvent to remove any remaining beads/debris. I'm not sure you need a new condenser as that's BEFORE the beads, but wouldn't hurt to reverse-flush that as well.
Noquacks
Posts: 12
Joined: Thu Jun 29, 2017 2:18 pm

Re: How to clean out dessicant beads from system

Postby Noquacks » Sun Jul 16, 2017 10:35 am

Thanks, cusser! That confirms my suspicion. I will leave the condenser and get new drier and put in new exp valve. Should I flush out liquid line in BOTH directions? With a simple air compressor, blasting in both directions?
Also, I heard never to use solvents like brake cleaner/mineral spirits, acetone, etc. Whats your favorite flush solvent?
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Cusser
Posts: 221
Joined: Sun Apr 24, 2016 6:29 am

Re: How to clean out dessicant beads from system

Postby Cusser » Mon Jul 17, 2017 8:21 pm

Noquacks wrote:Should I flush out liquid line in BOTH directions?


Reverse flush should be plenty. I like to collect the liquid flush in a bottle so I can see if there are any particles or debris.


Noquacks wrote:With a simple air compressor, blasting in both directions?


Yes, and best if the air is dry.


Noquacks wrote:Also, I heard never to use solvents like brake cleaner/mineral spirits, acetone, etc. Whats your favorite flush solvent?


I'm not a pro, only do this like every few years as I need to. I use this https://www.oreillyauto.com/detail/inte ... 40?q=flush

Important to use a solvent that will evaporate readily, like when you blow the remaining liquid out with your air compressor, and a solvent that will leave no residue.

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