Yes you sure can and I've done it, as long as it goes in the liquid port.
AC system
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Kestas
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The automotive a/c web sites popularly recommend using lacquer thinner and shop air. I've used it myself successfully.
I too have used Lacquer Thinner (LT) on badly contaminated systems with large volumes (badly contaminated for us means only the existing evap cores and lines will be reused/kept - TXV / Orifice, compressor, condenser, dryer/ accumulator, etc are all replaced).
Suburban with rear air has really long rear lines and uses about 2 to 2.5 lbs refrigerant. A 32oz flush isn't enough to clean the whole system. So use the LT first, forward flush first once, and then back-flushing both evap cores until LT comes out clean. Then we use the flush and let it evaporate. Sometimes we will use the 32 oz twice just to be sure the evaps are nice and clean of "black death".
Then let the system sit for a short while and then use nitrogen, or dry shop air (dry means dry, like you would paint with) to make sure all residual is gone. Add oil to each new component per specs and install. Then vacuum down and monitor for leaks. If none, charge and verify operation. If all good, send it.
Shoot, I've seen people use a warm soapy water attachment on a garden hose to backflush and flush systems. Then clean with plain water (hose pressure), run alcohol through it to dry it, and compressed air to finish it. It works, but I haven't ever done it.
Suburban with rear air has really long rear lines and uses about 2 to 2.5 lbs refrigerant. A 32oz flush isn't enough to clean the whole system. So use the LT first, forward flush first once, and then back-flushing both evap cores until LT comes out clean. Then we use the flush and let it evaporate. Sometimes we will use the 32 oz twice just to be sure the evaps are nice and clean of "black death".
Then let the system sit for a short while and then use nitrogen, or dry shop air (dry means dry, like you would paint with) to make sure all residual is gone. Add oil to each new component per specs and install. Then vacuum down and monitor for leaks. If none, charge and verify operation. If all good, send it.
Shoot, I've seen people use a warm soapy water attachment on a garden hose to backflush and flush systems. Then clean with plain water (hose pressure), run alcohol through it to dry it, and compressed air to finish it. It works, but I haven't ever done it.
So, for comparison, I've used 4 gallons once to clean a set of suburban evap cores in vehicle. Cost was around 40.00. One 32 oz can of flush was around 40.00. So 4 gallons versus (2) 32 oz flush. It took every bit of that 4 gallons to get the lines and the evaps clean. The rear is what really took the most time and effort. No way 64 oz total of flush would have done a through cleaning job.
The flush does the "final" job to remove whatever is left, which should be pretty much nothing, but maybe some oily acids if the LT didn't get it.
You would be amazed at how much contamination can accumulate in the system. You would think the orifice tube would catch it, but on this particular truck, the orifice screen failed and sent debris all through the system. Compressor was absolute toast, useless - along with everything else.
By the way, replacing the evaps can add so much cost to a repair like this due to dash removal, etc. that it is not worth it.
Oh, and that system ran perfect for years after that. Truck was sold and never saw it again, but I would think if it's still on the road, the AC is still working fine.
The flush does the "final" job to remove whatever is left, which should be pretty much nothing, but maybe some oily acids if the LT didn't get it.
You would be amazed at how much contamination can accumulate in the system. You would think the orifice tube would catch it, but on this particular truck, the orifice screen failed and sent debris all through the system. Compressor was absolute toast, useless - along with everything else.
By the way, replacing the evaps can add so much cost to a repair like this due to dash removal, etc. that it is not worth it.
Oh, and that system ran perfect for years after that. Truck was sold and never saw it again, but I would think if it's still on the road, the AC is still working fine.
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