Four Seasons 69994 Super Flush Solvent, 32 Oz/ 946 ml

Used to flush out automotive ac lines. Worked great

I used this product after our A/C compressor shorted out (burned out). After a burnout, the mineral oil becomes acidic and all traces of it need to be removed from the system or your new compressor and its motor windings won't last long.Since we were replacing the copper evaporator coil with a new aluminum one (24 year old Carrier slant coil), I just cut the suction and liquid lines at the evaporator and outside at the condenser. Next, I dumped the solvent into a siphon canister and using a CO2 B-tank to blast the solvent through the lines outside into a bucket with a towel in the bottom of it. Needless to say, it flushed all the crap out of the lines and the lines dried out quite quickly with no film residue. The towel in the bucket was covered in UV leak detector dye which was injected in the system years ago to find a leak in the liquid line a few years back.Next, we brazed in the new liquid/suction line for the evaporator and then pressure tested it with nitrogen. On a side note here, you young guys in the trade that think you can pressure test with CO2 or Argon gas, don't because those gases are horrible at leaking out through the service hoses under pressure. You won't be able to tell if you have a leak or not in a reasonable amount time if you use anything other than nitrogen gas.Now brazing with CO2 is perfectly fine and saves on having to refill your nitrogen tank. Also, a CO2 tank of similar size also holds more because its a liquid and then expands to gas unlike your nitrogen tank which is already a gas!Anyway, we pressure tested with the Testo 550 manifold and had no leaks (held pressure for 30+ minutes and not even a -0.1psig in pressure) so were ready to move on to the condenser when we get time away from putting in hay for our cattle.We're converting from R22 to R407c (Copeland POE compressor) for this old 3-ton Carrier A/C system so its quite important for the system to be 100% leak free. These new refrigerants (R424a/R407c/etc.) are a mixture that has quite a bit of temperature glide meaning if it leaks all the refrigerant has to be extracted and replaced because it leaks out at different rates thus changing its original composition and becomes less efficient! Its a different animal than R22 or R410a which has almost no temperature glide so you can just top the system off if its a little low and move on.I really like the product and highly recommend it but hopefully I won't need to buy anymore due to a compressor burnout because I really loathe A/C work 😉

It flushes

Installers didn't want to reuse the tubing running through finished walls and ceilings when my mini-split AC died and would only quote super expensive replacements that involved running all new tubing. I decided to replace the mini-split myself and re-use the existing tubing. Since the refrigerant was changing, I needed to give the old tubing a good flushing. I bought a kit that uses a compressor to blow solvent such as this through the tubing to clean out any old refrigerant and oils.I used this and blew it through the lines. I assume it worked but have no real evidence or frame of reference to say for sure. The new heat pump is running fine, so far. My only real knock against this is how expensive it is. This doesn't seem like the type of product that should cost $22. So, 4 stars from me. One off for lack of value.

My first use of 69995 after using a variety of other flushes over the last 2 decades. Was hesitant to purchase due to higher cost and absolutely no availability anywhere locally except to order. Finally decided to purchase Four Seasons after reviewing technicians comments on auto A/C repair forums, and the Four Seasons emphasis on fast drying time.In application this flush makes other solvent based flushes not as-cost effective as they take so long to fully dry out - even in hot low humidity weather and a constant flow of low pressure compressed air left on continuously for hours.This one is Essential, especially if you're working on one project at a time, and/ or need to get back in service the same day.Four Seasons has no residual indication of solvent / oil / or anything else left behind including odor, and dries quickly - literally.And equally important - as they claim - a little goes a long way.Granted I had no appreciable amount of compressor wear silt in this instance, but my total evaporator flush time was rather quick with no nagging worry about trapped pockets of old oil/flush still remaining. I really liked the way it cut through PAG oil and made flushing an evaporator in place without the usual nagging afterthought of worry the comes after reassembly - 'did I really get it all out?'The reason I flushed short of compressor failure was to rid the system of PAG 46 and convert back to PAG 150 for use with my GM HR6 compressor. Flushed with small amount 3 separate times, with no detectable compressor wear silt residue at all during second flush, but did it a 3rd time in both directions again just to ensure that I got any remaining silk or Oring debris from 120K accumulated miles of service. No discoloration or any sign of debris on 3rd flush.Used 1 & 1/2 Qts total.