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Carette 4500 PSI Compressor Report

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    The Carette 4500 compressor is a Chinese compressor that seeks to fill the price performance gap between “big boy” dive compressors and Shoebox compressors.

    Mr. Wang has kindly supplied a demonstrator unit for testing. As a demonstrator unit rather than a final production unit, the test unit may not match the appearance and configuration of the actual shipped units. This one included a PMV, high pressure air filter unit and automated condensate drain system. I do not know if those features will be in the final configuration. I have been told that the external finish will be better on the actual units. Also, the crankshaft bearing and rods will be more durable than those on this demonstrator.

    I had hoped to be testing a unit that is an actual production sample, but because this is a demonstrator unit, bear in mind that the shipped product may differ from what I am testing. This does affect my ability to report whether the machine is a thumbs up or down. If the production units are worse than what I’m testing, I certainly wouldn’t be happy, nor would our forum members. On the other hand, I am getting very appropriate and encouraging responses from the manufacturer regarding my findings. Mr. Wang (Sincere) is actively improving the machine based on my comments.

    For instance, he was ready about make changes regarding current draw based on my measurements. I don’t think changing the current draw would be worth it, if it slows the compressors. Also, the amount of oil I see in the condensate was already a known issue on this demonstrator. They already have a different component that cuts the oil bypass to 1/3 what I’m seeing. The oil bypass even on this demonstrator isn’t horrible. He’s also planning how to integrate the air filter on the compressor frame. It’s that type of desire to make a better product that I want in a manufacturer.

    Rather than the demonstrator being perfect and production machines worse, we could end up with better production machines. However, I can only report what I am seeing and won’t speculate on what will actually ship to you. On the other hand, I have the impression that Mr. Wang actually does intend to deliver what he promises.

    Main Topic Posts Index

    Unpacking, Parts, Feature Details

    Oil, Water, Initial Run-in

    Rifle Air Cylinder Filling Test

    Great White CF Tank Top Off & Fill From Empty Tests

    24 Hour Torture Test


    The Carette 4500 compressor was well packaged to survive the trip from China. It was not on a palette, but the FedEx delivery man was able to lift the crate by himself.

    Lifting the hinged lid revealed the compressor and several bags of parts. The small manual was only in Chinese.

    I really liked how neatly the compressor was bolted down to the bottom of the crate using wing nuts. Rubber strips protected the finish from the wood securing strips. That type of detail was echoed throughout the initial inspection of the compressor. It looks well put together rather than something thrown together in someones garage.

    I was able to lift the compressor out of its crate using its handles without needing assistance.

    Foster fill whip, high pressure hoses, and various fittings were neatly bagged. There are no instructions on how to add the fiddly bits to the compressor and high pressure filter.

    There was even a DIN fill whip and DIN/Foster adapter in the package, but I don’t know if that would be a standard item. I think they were making certain I had everything needed to hook things up.

    Shipment included a large, beefy, high pressure filter cylinder. It’s a user pack style that doesn’t use cartridges. Cartridge was already packed and a spare packet each of activated carbon and molecular sieve were also in the shipment.

    For size comparison, here it is next to an Alpha filter. Note the bleed valves and PMV on the Alpha.

    There are already multiple videos and pictures of the compressor on the web. So, I’ll just show what I found notable.

    The compressor is a two stage design. Casting is definitely different from Mrodair’s compressor. The machining, fit and finish on this unit are considerably better than the Airmax Extreme’s. This “demonstrator” unit has a PMV and automatic bleeder installed. I’m told the production machines will have better crankcases bearings and rods than the unit I have for testing.

    That said, this is a complete, self contained design without need for external water buckets or running water for cooling. Power for the compressor is 120 volts (despite a 220v label on the cooling fan).

    Notice the relatively large water oil separator. It’s actually big enough to do a good job and not need bleeding as often.

    The PMV is mounted on the water oil separator. It is adjustable via the locking nut and adjustment bolt on its end. Ideally, this would actually be AFTER the high pressure drying and oil filter. Because the filter unit is separate from the compressor, I can understand why it was mounted here. If the threads were compatible, I would move the PMV to the outlet of the high pressure drying filter for maximal effect. BTW, the brass knob atop the PMV acts as the fill whip bleed.

    The little silver bolt just below the PMV, on the water oil separator covers a burst disc. Yes, this has an overpressure safety. The disc will rupture and help avoid catastrophic failure. The MrodAir completely lacked any overpressure safety measures. The Carrette 4500 costs more to make for at higher quality and safety.

    There is a real motor control box that encloses all the electrical. You can’t accidentally touch bare metal conductors like you can in the Airmax Extreme. The motor control safely does NOT re-engage the motor if AC mains power is lost and regained.

    Automatic drainage of the water & oil separator condensate combined with auto shutoff at desired pressure allows unattended operation. My Bauer Jr has zero automation and didn’t even come with a motor control box. This machine lets you set both interval between bleeds and how long each bleed should last. BTW, the bleed will likely scare you the first time it opens.

    Pressure gauge and automatic shutoff. Didn’t come filled with glycerin.

    Cooling of compressed air improves water separation and keeps the cylinders cooler. This compressor has coiled tubing both between stages and again before the water oil separator.

    nice… Not as big as the coils in my Bauer, but these only get warm (not even hot) after over an hour running at 2500 PSI. For this machine’s air compression rate, they seem adequate. I’ll recheck once I do full pressure testing.

    Look at how nicely the cooling jacket is finished and fitting to secure the temperature probe. Little details make this stand apart another machine where the temp probe was simply potted in a hole with glue. Sure looks a different level machine.

    Initial impression from inspection is that this machine adds features, design & safety changes I thought were sorely lacking on the Airmax Extreme. This is NOT an Airmax Extreme. The Carette is obviously a different design and seems a better build. Very promising….


    Compressor arrived (thankfully) without oil or coolant. You really don’t want oil in the machine during shipment. The coolant is shown as antifreeze on the youtube video, but I was told water. I’ve filled with water since that has a higher heat carrying capacity than antifreeze.

    I used Bauer synthetic compressor oil. The crankcase label indicates 300 ml and that is about what I poured. Oil level is easy to see as one fills the crank case. They’ve made the label and observation dot indicator very easy to understand. Just fill to the top of the red dot and no further.

    Fill the cooling system is a little trickier because you need to minimize air. First tip the entire compressor backwards and use some blocking to keep it tilted about 5 degrees. The tilt helps get the radiator full filled and cleared of air.

    Be sure to avoid the protrusions at the bottom of the water pump and water oil separator. You don’t want to break those by making them support the compressor’s weight.

    Disconnect the coolant tube from the high pressure cylinder cooling jacket. That would be the tube going from the low pressure cooling jacket to the high pressure.
    Connect a spare piece of tubing to the high pressure cooling jacket inlet to fill the system. I used one long enough to let me siphon the water into the system. By the green color of the residual coolant in the machine. I could see they had used antifreeze in this unit. (It had 30 minutes on its timer)

    Once coolant fills the entire system, reconnect the original tubing.

    EDIT: Rather than siphoning or using a syringe, I later found it was a lot easier to fill and de-air with a squeeze spray bottle to pump coolant into the compressor. This let me put in coolant without injecting air. Pressurization from squeezing the spray bottle also drive air that is in the cooling system out. Open the spray bottle cap and route the tubing from the low pressure side drain back into the spray bottle. Squeeze, squeeze, squeeze and you fully fill the cooling system.

    Once oil and coolant are filled. You can proceed with adding the fill whips, bleeder valves, etc.

    Initial run-in on a new Bauer is 15 – 20 minutes at zero load.

    I’m letting this compressor properly “bed in” at lower pressure before moving up to higher pressures.
    30 minutes at zero load, then 2,500 psi for a total nearing three hours thus far. The cooling system works. Nothing is hot to the touch. That’s including all the high pressure pipes.

    After being spoilt by the Bauer’s self-contained cooling, you can’t go back to a water bucket or hose. The convenience of just plugging in and turning on the compressor is delivered by this Carette 4500.

    The Carette is quiet compared to my Bauer Jr (which is super quiet compared to the Airmax Extreme)

    Bauer noise is 88 dB at normal operator distance and 85 dB at one meter
    Carette noise is 80 dB at normal operator distance and 74 dB at one meter

    That is quiet enough that the blast from the auto condensate drain startled me the first time it bled.

    Power consumption
    unloaded is 12.2 amps / 930 watts
    at 2500 PSI is 14.4 amps / 1100 watts

    I may have to move to a 20 amp socket for full pressure testing, but this is a far cry from the crazy amperages needed by an Arkansas machine.


    After completing run-in at lower pressures, it was time to move forward with full pressure testing. Because I wish to protect my equipment from both moisture and oil contamination, I did all fill testing with an Alpha filter between the compressor and device to be filled.

    Although I could have tested with the Carette included filter, I decided to use the Alpha because it is a proven unit that protected my gear even against the horribly fouled output of the Mrodair Airmax Extreme machine. Remember, that one put out so much oil and moisture that I could barely see across my garage due to the suspended fog.

    The Carette 4500 did not fill the air with fog despite two hours of run time. It still did put out some oil in its condensate, but it was pretty minor compared to what I was seeing with the “Arkansas fumigation” unit. I knew the Alpha filter can handle this easily.

    Test Setup was as below. A white plastic tray was positioned to catch condensate drainage. Alpha unit is lashed upright for best function.

    As an aside, an extra bleed valve at the Alpha output is needed because I was going to test fill a rifle directly. If you order an Alpha be sure to let them know whether you are also going to fill rifles directly rather than just tanks. If you don’t get this extra bleed valve, you can’t bleed down the fill whip. The input bleed valve on an Alpha does NOT bleed the far side of its PMV.

    Anyways, the test setup allows measurement of electrical power usage, temperature at two points, and ready inspection of condensate. An SPL meter was also used at 1 meter to check noise level.

    This picture is actually for the Great White testing, but just image an AGN Vulcan attached to the fill whip instead of the Great White.

    The setup has two PMV’s. Typically, you would only have one PMV just before the final filter output. This complicates interpretation of timing when filling a small cylinder like a rifle’s. The compressor needs time to…

    1. Build up enough pressure in the water separator to open the compressor’s PMV and begin releasing air out of the PMV outlet. This takes 43 seconds to open at 2500 psi.

    2. Pressurize the alpha filter who’s internal volume is that of an air rifle cylinder. Its PMV opens at 1800 PSI. This is at 92 seconds after compressor startup.

    3. Finally, cleaned air is delivered to the fill whip.

    Topping up a Vulcan from 150 bar to 250 bar took a total of 307 seconds from star to finish. This includes the time to pressurize the water oil separator and alpha filter. One cycle of the auto vent also added about 30 seconds to the fill time (since that drops pressure to near zero)

    So, in terms of actually filling action time, we’re looking at
    total 307 to top off from 150 to 250 bar
    of which 307 – 92 – 30 = 185 seconds are actually time filling the air cylinder.

    Pressure gauge reading on the Carette matched the AGN manometer pretty well.

    So, yes you can pretty conveniently fill a rifle directly with this compressor. The total time is way faster than a hand pump. The auto shutoff means you could conceivably let it fill without watching the process, but total time is short enough that I think it would be silly to walk away.

    Would I used this compressor without a filter? No. by itself the compressor (with a PMV) does a very good job of separating out oil and water, but a separator cannot do the entire job. I would still put a filter between this and any equipment I wish to preserve and use safely. On the other hand, I would say the same about any compressor that does not have its own high filter for moisture and hydrocarbon removal.


    The Carrette 4500 can easily top off a Great White in a reasonable time. 72 minutes total to top up from 2750 to 4500 PSI. Machine stayed quiet and never sounded strained, nor did it get hot. Very impressive was how cool the air remained, even that coming out of the high pressure cylinder output. The lower temperature means less cylinder stress AND better water separation.

    Test setup was already shown an earlier post. I set the automatic condensate drain to every 10 minutes. You don’t have to hang over the compressor while it works. 72 minutes is a while, but you can go about your business while the machine works. Without the manual bleed, you would need to bleed the machine every 10-15 minutes.

    Temperature probe on high pressure stage output pipe

    Here are some data points. I didn’t get them every 100 PSI because there really weren’t huge changes in power consumption or noise. The steady amperage level was surprising to see as pressure increased. They really HAVE geared things down so power draw and heat are well balanced with air production speed.

    00 min, 2800 PSI, 14.8 amps, 1136 watts, 76 dB
    04 min, 2900 PSI, 14.6 amps, 1120 watts
    08 min, 3000 PSI, 14.2 amps, 1097 watts, 76 dB
    12 min, 3100 PSI, 14.0 amps, 1073 watts
    19 min, 3300 PSI, 13.8 amps, 1059 watts
    32 min, 3700 PSI, 14.0 amps, 1070 watts, 76 dB
    39 min, 3800 PSI, 14.0 amps, 1068 watts
    52 min, 4100 PSI, 14.1 amps, 1083 watts
    57 min, 4200 PSI, 14.1 amps, 1084 watts, 76 dB
    60 min, 4300 PSI, 14.2 amps, 1089 watts
    66 min, 4400 PSI, 14.1 amps, 1069 watts
    72 min, 4500 PSI, 14.5 amps, 1089 watts, 76 db

    Air output temperature at the high pressure cylinder was 35.3 C at 4500 psi. This is incredibly cool for air coming out of the high pressure cylinder AND that is before going through the cooling tube. The water oil separator never heats up! Lower temperature function will reduce risk of dieseling and make water separation more efficient. Instead of separating at an elevated temperature’s dew point, the Carette does its separation at a lower temperature. That lets it wring out more water than if it were trying to do it at a higher temperature. You can comfortably hold either high pressure tube during operation. It’s simply amazing to for the air to remain so cool during compression.

    The amperage draw, even at full pressure, is low enough for the average household receptacle. Ideally, a 20 amp circuit would give more headroom, but I had no difficulty at all on a 15 amp circuit.

    The cooling system is well matched to the thermal load. It keeps the compressed air and cylinder jackets comfortable to hold. The 1st stage cylinder fins are the warmest portion I could find at 51c. Tons of air motion keep the motor housing at 38 c.

    Pressure gauges matched up well when Great White gauge read 4500 psi

    Here is the condensate collected after doing the entire top up from 2800 to 4500 psi over 72 minutes.

    There is some oil that has been separated out in the condensate. The output air would have just a fraction of that in the condensate — easily handled by the activated carbon of a filter. Also, even more telling. a ray of sunlight entering the garage window didn’t light up any suspended fog despite the 72 minutes of operation.

    The Great White was then bled down to empty. That takes quite a while.
    Filling from empty was surprisingly linear in terms of PSI gain/hour

    1:00 Hour 1500 psi
    2:00 Hour 3100 psi
    3:06 Hour 4600 psi

    The condensate drainage for the entire 3 hour, continuous run looked like this…

    Tellingly, bleeding the bottom of the Alpha filter yielded no visible output at all even after the three hours. This differs dramatically from what would happen with the Mrodair Airmax Extreme. That compressor failed to adequately separate water and oil from the air. Whenever I bled the bottom of the Alpha with the Airmax, material was expelled every time. The Carette’s separator is doing an admirable job if I am see NOTHING come out of the Alpha’s bottom vent.

    We still need endurance data, but thus far, this machine is working better than expected. The Carette 5400’s gentler speed is likely to reduce mechanical wear rate. It was a really smart choice to slow down the compressor. You can’t build full scale dive compressor robustness and speed at this price range. However, the Carrette 4500 is appropriately engineered run a bit slower and get around electrical, mechanical, and water separation issues. The fill rate is still quite reasonable, and if one gets the auto condensation bleed and shutoff, once can just let it take care of itself during filling.


    Compressor was run 24 hours non-stop to examine how it fares under prolonged operation. This is roughly the equivalent of two years of topping up a Great White once a month. I used the PMV as the test load because it was not practical to repeatedly empty and fill a tank continuously. The PMV at 2500 PSI provided a substantial load that could be sustained for the entire run. The compressor remained cool and NEVER stopped during the entire 24 hour run.

    Auto drain was set for every 10 minutes, 1/2 second opening

    Tray was set up to trap condensate. We already know this demonstrator puts out some oil. I don’t want that getting all through the garage and we want to examine how much oil is being blown by. (Sincere says the production units should have 1/3 oil blow by of this unit)

    Output of the compressor was wrapped to go through multiple layers of paper towel to act as a “tell tale” for how much water and oil were getting past the separator. After an entire 24 hour run, we should be able to tell if excessive amount is getting through.

    The run was uneventful. Compressor ran unattended for most of the hours. It was really nice having an auto drain instead of manual bleeding. I could sleep overnight as it took care of itself. Also of note, the outputs of the manual and auto drain are both amenable to having some sort of tubing attached to avoid getting vented condensate all over the floor. By contrast the Mrodair bleed valve would simply spew onto your hand and floor. There was no way to trap the output.

    Output air temperature of the high cylinder stayed at 105F or lower! All the cylinders were comfortable to the touch throughout. This compressor keeps itself and its output air cool. That’ better for machine lifespan and water separation efficiency.

    My Bauer Jr can’t be run for 24 hours continuously. This Carette did so without a hitch.

    How much oil came through the system? The is my catchment tray after 24 hours operation.

    Some oil clearly gets by. It’s not a huge amount. The oil is darkened, but not black/dieseled. Air in the garage has the scent of Bauer synthetic oil. No fog bank effect was seen filing the air.

    Mind you, this is 24 HOURS of continuous operation producing this much condensate output. Water was mainly gone, but you can see the film of oil. If the production units can get this down to 1/3, I’d be very happy.

    Sorry, I cannot verify the reduced oil blow by in the shipping units without final spec parts in this compressor unit.

    Already, it is promising even at this amount.

    More importantly, how much water & oil are getting past the separator? Uwrapping my tell tale revealed…

    I had expected to see very noticeable accumulation. After a whole 24 hours, some moisture and oil spotting has just got to be there I thought. At first I could nothing. Only after fully unrolling and comparing the outermost and innermost layers could I see a difference. Just a little oil gets past the water oil separator. A filter with molecular sieved dryer followed by activated carbon will easily handle this for multiple tank fills.

    24 hours continuous operation endurance and degree of separator efficiency impresses me. I expected the separator would be good based on the low air temperature, large separator size, and PMV, but this degree of separation was better than I could have imagined.

    We still need to look inside and see how the run hours have worn the compressor. That will be during my tear down. One hint we already have is the condition of oil in the crankcase. Remember how just a few hours run time on the Mrodair turned the oil almost black? This is what I see in the Carette’s oil window after 30 hours operation.

    The oil is darker, but not blackened from dieseling/mechanical wear.

    We’ll verify during tear down.


    High Pressure Cylinder

    Coolant was drained from the compressor and coolant lines detached. High pressure lines were pretty standard high pressure fittings with tapered ends and compression nuts.

    The heatsink atop the high pressure cylinder head is secured by only one grub screw. However, on this unit, that grub screw was near the position of the thermal sensor and thus not visible during initial tear down. Also, be mindful of the short leads for the thermal sensor. You’ll either need a right angle phillips driver, or simply detach the sensor from the cylinder head as you remove the head.

    Grub screw of heat sink. The screw just below and right of it is one of the heat sink securing screws. Once you loose the grub screw, the heatsink slips right off.

    NB. Removing the heat sink may suddenly free the four stainless steel washers that may not have come out with the cylinder head bolts. Those four stainless steel washers are SINGLE USE ONLY. They must be replaced with new ones when the cylinder is reassembled. Otherwise, coolant will leak out around the bolt heads.

    The cylinder head with heatsink removed reveals the piece under which the reed valve lives. I could never get enough torque to open the silver colored piece. It is cranked on hard. Resecuring the head to the cylinder didn’t help. I did not force it with a breaker bar because I can easily hear the valve wafer moving freely inside. No reason to break open until that valve needs replacement.

    Bottom of high pressure cylinder head. A fiber washer surrounds the air inlet/outlet, but that is not the main pressure seal.

    The high pressure seal is formed by a higher temperature o-ring that is properly sized and fully captured within a groove. The larger o-ring is for coolant seal.

    Notice that the bolt holes go THROUGH the water jacket. This is a crucial detail that affects how you put the cylinder back together. The bolts and their stainless steel washers must be water tight. This is why the washers must be replaced with new ones. Deformation of the washer as you torque the bolts tight creates a water tight seal. Once the washers have been used, they will not create a seal if you try to use them again. I tried. Definitely leaks.

    NEVER disassemble the high pressure cylinder unless you have spare stainless steel washers to replace the four used to secure the high pressure cylinder head. The low pressure cylinder does not share this issue because its bolts do not go through the cooling fluid.

    The actual working cylinder is a metal, cylinder nsert. Four bolts and washers secure the high pressure cylinder to the crankcase.

    We worry about high pressure rings wearing out. Those were a quickly burned and destroyed phenolic rings in the Mrodair. What does this compressor have? Three, four rings? Are they metallic rings? Are they plastic?

    Pull the cylinder and we see….

    Wow! NO rings. This thing works by letting a precision ground piston slide inside a well fitted cylinder. There are NO rings to wear or burn out.
    Sincere says the rod and cylinder on this demo unit are not as hard as those that will be in the production units. I really don’t see anything amiss in this high pressure cylinder after over 30 hours run time. No dieseling carbon buildup. There is just a tiny bit of darkening at the end of the piston.

    The bottom end of the cylinder is nicely finished and readily guides the piston back into the cylinder. No need to individually ensure each high pressure ring is safely into the cylinder without deformation. There aren’t any rings to damage. Just guide the piston in gently.

    I am impressed by how the high pressure cylinder is built. A high level of parts precision is needed to dare such a design.

    Low Pressure Cylinder

    Onward to the low pressure cylinder. The air filter unscrews by hand. Four bolts and washers hold the cylinder head.

    Keep a grip on the cylinder head as the bolts are removed. It will come completely loose when the bolts are gone.

    Bottom of the cylinder head is familiar looking. An output reed valve lives under that valve plate.

    The inlet reed valve is also familiar. Remember that those index pins are actually loose. Don’t drop and lose them.

    OMG! What is this? How could there be so much oil bypass? This is worse that I ever saw on the Fumigator Extreme. Why didn’t I see more oil in the output if this is going on?

    One wipe with a paper towel and….

    No it isn’t oil. It is a pool of rusty water.

    It has corroded the cylinder where it pooled and there is even a palpable deep pit above where the water was collected.
    The cylinder walls look awful in this image, but a lot of that darkness wiped away. The cylinder walls otherwise look like they started out well polished and smooth.

    After wiping clean. It looks much better. I also moved the piston further into the crankcase after wiping. That is why you see that residue line. The rings were definitely selling against the water.

    I don’t understand how so much water accumulated in the low pressure cylinder. I checked the coolant o-rings and their seats. All look fine. I don’t think the water got in from the cooling system running. It is a mystery.

    So, overall, the compressor, especially the high pressure cylinder is impressively built.

    The low pressure side, is not bypassing large amounts of oil, but there is this puzzling pooling of water in the low pressure cylinder.

    CONFIRMED. The nasty water in the low pressure side is residual condensate from the long, 24 hour run. Longer run –> more condensate to clear.
    I did NOT do any post run clearance procedure after the 24 hour test.

    Recommendation from manufacturer now is to run the compressor 5 minutes with vents open to clear any condensate after EACH use of the compressor.

    Running the compressor with the water oil separator valve open for 5 minutes DOES indeed clear out any condensate that may have collected in the low pressure cylinder. This post-run purge should be done at the end of each usage session.

    Failure to do a post run purge may result in what you saw above. With the post-run purge, the low pressure cylinder should remain in good shape.






    The Carette 4500’s motor control box has all wires passing into it via nicely snug pass throughs. The 3 prong, 120 volt AC power cord is permanently attached. No exposed bare wiring or electrical contacts are present which make this much safer than the Fumigator extreme’s ungrounded metal chassis and touchable, bare 240 volt contacts.

    The mother control box and its control panel were opened for inspection. The cover is sealed with a foam gasket around its perimeter. No smell of overheating or burning was detected when the control box was opened. This is despite my 24 hour torture test run.

    Wires appear appropriate for the loads. All connectors are orderly and bundled in looms. Definitely not a rats nest. This is well planned and executed wiring. Clearly NOT built with absolute cheapest construction.

    A proper contactor handles the motor load. There is a power supply to run the thermal sensing circuitry. They didn’t go cheap and try to run everything with mains voltage.

    Yes, the AC ground IS actually connected to the chassis to protect the user.

    This is a better motor control box than what I built for my Bauer Jr.


    Because, we discovered residual condensate had remained in the lower pressure cylinder after its 24 hour torture test, there was concern regarding how the low pressure cylinder would fare long term.

    I DID NOT do anything special with the compressor at the end of the 24 hour run. I merely turned it off and bled down the vents.

    HOWEVER, we now know the compressor should be run with its vents open for 4-5 minutes to clear the cylinders after EVERY usage episode.

    I tested the effectiveness of this post run purge by intentionally loading the low pressure cylinder with 3 ml of distilled water. This is way more than was found during cylinder inspection post 24 hour run. This amount is more than the cylinder is likely to ever condense. If the purge procedure can clear this, it can clear anything the compressor can accumulate.

    The compressor was reassembled and run for 5 minutes with the water oil separator valve open. Water did come out of the separator.

    Upon re-inspection, of the low pressure cylinder, all the water was gone.
    I did a backup test of running the compressor with load for one hour, followed by a five minute open valve “purge.” The low pressure cylinder at the end of that was completely free of water. Only a very tiny bit of oil was found in the cylinder.

    YES. Purging by running for five minutes with valves open works.

    The rusty water I found could have been prevented by following the purge procedure. Rather than doing the purge every 2 months only during prolonged idle storage, the purge should be done AFTER EVERY USAGE EPISODE to keep the cylinders in good shape.


    Actual content will replace these place holders over next few weeks.


    Test the machine crazily,please! Do not let it rest! Torture it please!


    Dear guykuo, is there a need for a ransom collection???

    Just asking????
    LarryW 😉

    quote LarryW22:

    Dear guykuo, is there a need for a ransom collection???

    Amen. I was beginning to think I was the only one who felt this way.

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