Altaros Compressor
Hello,
we would like to take this opportunity to introduce our Altaros compressor for the home bottle filling on high air pressure up to 300bar/4500 psi .
At the same time, we want to answer your questions and ask your opinion on our compressor. We welcome all comments and type of information that would interest you and should be on our web.
Or some technical improvements that you would like on compressor in the future.
Here is few photos:
Compressor video test with temperature meassurements
Parameters.
Output pressure Max 300bar, 30MPa, 4500 PSI
Input pressure Min 5bar, 70 PSI
Max 10bar, 145PSI
Size (Height x width x depth) 30x30x60 cm 11.7 x 11.7 x 23.6 inch
Weight 5 kg 11 lb
More detailed information can be found on our website:
Or in our manual:
Thank you for your comments, which will surely help make the compressor even better than it is now.
All Replies
:hoot:
Dear Pops…
We are not fooled! Tossing us these tiny tidbits of information won’t work here…we have ways to make you talk…talk long and hard!!!
Kindly ‘Ol Uncle Hoot:
Got some time to wait until the garage gets my vehicle checked and tyres changed, I’ll use this for another post concerning the Altaros compressor booster unit.
As usual, get a drink, maybe something to eat, it’s going to be a little long. I recommend to have the pictures Altaros posted in his initial writeup of this thread at hand, makes it easier to understand and avoids me posting them again, making a long writeup even longer.
Let’s get to it:

I’d like to start out with the working principle, which I think is necessary to explain in order to understand the whole system. I’ll try to use the original terms, Altaros use in their user manual, as far as possible.
The unit is – inside the plastic case – composed of three cylinders, as we can see from the cutaway pictures. The central cylinder is the one with the big diameter, I’ll call it the „driving cylinder“. The piston consists of a big diameter disc with a rubber o-ring around it in order to seal. Connected to this driver piston on the right side is the „mid-pressure“ piston or the first stage. To the left, we find the high pressure piston or the second, and final stage each one moving in it’s own cylinder. Each one of the both outer cylinders has a second cylinder around it and an air cushion in between.
Sitting on top of the driving cylinder housing, we find a spider-like thing called the „8. control unit“, with a lot of hoses coming out, as well as the 12V power adapter connection, and some electric connectors and cables.
Let’s follow the airflow:
input from the workshop compressor using a quick detach fitting on the outside of the booster unit housing, called the „6. input quick release air pin“, which is directly fitted to the „11. filter/water separator“ on the inside of the „1. outer casing of the device“.
The air passes from the worksop compressor output through the quick detach fitting through the „ 11. filter/water separator“. This is the first stage water separation unit, under the same pressure as provided by the workshop compressor.
From there two outputs using black rubber hoses:
1.) to the left connecting to the „13. Air flow setting screw“ and from there to the „8. control unit“. As to my understanding, the air flow setting screw alters the air debit delivered to the control unit, in order to set the working speed of the driving piston. The pressure should be the same as delivered by the workshop compressor.
2.) to the right connecting to a second moisture filter, called „12. final protection from humidity“. A filter consisting of basically an end cap with input fitting, filter, tube, silica gel with color indicator on the inside, filter, end cap with output fitting and rubber hose to the first stage or „mid pressure“ cylinder. Same pressure, as provided by the workshop compressor.
And here’s where the first of the two pressure cylinders, the mid pressure cylinder comes into play.
Let’s take this as the beginning of a cycle, the driving piston is on the left end of the driving cylinder. The mid pressure piston is pulled all the way to the left side as well, leaving room in the cylinder and opening up the mid-pressure chamber for the air coming from the „12. final protection from humidity“.
Two things happen simultaneously:
1. The driving cylinder now starts to move to the right, pushing the mid-pressure piston in the right cylinder in the same direction, so it compresses the input air and sends it through the second fitting and the white, more rigid mid-pressure hose to the high-pressure cylinder input fitting on the left cylinder.
2. At the same time, while the mid-pressure piston is moving to the right, compressing air, the high-pressure piston in the left cylinder is moving to the right as well, opening up the high-pressure chamber to allow for reception of the input air coming through the white hose from the mid-pressure cylinder on the right.
This describes the end of the first half-cycle.
During the second half cycle, again two things happen simultaneously:
1. The driving piston reverses direction and moves to the left, making the high-pressure piston in the left cylinder move to the left, compressing the mid-pressure air it had received from the mid-pressure cylinder on the right, during the previous half-cycle. The now high-pressure air in the left cylinder exits through the „5. output high pressure hose“ to whatever you have connected it to (air gun, diving cylinder,…).
2. while moving to the left, the driving piston pulls the mid-pressure piston in the right cylinder to the left, opening up the mid-pressure compression chamber for new air from the workshop compressor.
This describes the end of the second half-cycle, the whole thing starts all over again.
In a simplified way of seeing the process one could say the compressor is stacking the output air cycle after cycle in the recipient.
Now, how does the driving cylinder know when to slide left or right and what is powering it? Here’s where the spider-like control unit comes into play. One air input, 4 air outputs. Some electrical wiring.
Two of the hoses are connected to the frame of the driving cylinder, one to the left, one to the right. Air flows only through one of these two outputs at a time. When air from the input is directed, say to the left frame, pressure is building up in the left side of the driving cylinder, pushing the driving piston, along with the connected mid- and high-pressure pistons to the right.
At the end of the piston travel, an end-contact tells the control unit to stop air flow to the left side and start air flow to the right side of the driving cylinder.
This pushes the driving piston and the connected mid- and high-pressure pistons to the left, until the end contact on the left side of the main cylinder inverses the air flow again and so on, and so on.
What are the two other outputs for?
They use part of the air to create an airflow between the outer and inner cylinders of each side alternatively. Remember, in the beginning I said that both, the mid-pressure cylinder on the right and the high-pressure cylinder on the left each are located in a second cylinder housing. We can see this on the cutaway pictures Altaros had posted, as well.
Every time the piston in one of the two cylinders is moving towards the extremity and thus building up pressure, the air flows around this same cylinder for cooling, i.e. air for the right cylinder while pistons are moving to the right and air for the left cylinder while pistons are moving to the left.
I can not say for sure where the air used for cooling comes from, but to me the most logic solution would be to use the air from the side of the driving piston which is currently not pressurized. For example, while moving to the left, the pressure is applied to the right side, the air on the left side needs to escape, otherwise the driving piston would not move.
This exhaust air used for cooling makes the repeating hiss we can hear when the unit is working, which gives it this Darth-Vador kind of breathing sound.
Well, hope this was understandable, if not, feel free to ask.
In the next writeup, I will come to why not only pressure, but also airflow is important, Knife has stated it in a very understandable way before, I’ll just try to put it in relation with the working principle of the unit. Furthermore, some more thoughts on what the airflow setting screw is good for, some hints for a successful first operation and a small wishlist of what I’d like to see more on this compressor booster unit.
Until then , cheers
Edit: this is going to be a long one, but I hope worthwhile reading, get a drink before starting :winkn: – edit end…
Hello all,
Ordered and received mine just after Hoot had and at about the same time as Knife.
When ordering, the sales guy over at Altaros asked some basic questions on required configuration concerning power adapter and shop compressor connection type, as well as intended use.
I’d say the shop compressor connection type question came from the experience made with good ol’ uncle Hoot’s, just some posts before. That shows their rapid reaction and adaptability, making use of lessons-learned.
Next, the booster unit arrived, but – oh no – the bleed screw on the silver metal block did not survive the transport. Head sliced off, threads still in the hole. Not Altaros’ fault though, the unit was really well packed, with foam, plastic and all the bells and whistles. Wrote an email and had an answer within an hour. The sales guy explained to me that if I managed to turn the remaining part, the one stuck in the thread, using a straight-bladed screwdriver, he’d send me a replacement bleed screw, otherwise of course the whole metal block (wow). Furthermore, he explained how I’d be able to fill safely nevertheless, in case I had a Scuba fill line using the fill line’s bleed screw for bleeding the line after filling. He was really sorry for the inconvenience (even though it was not their fault). The next day I saw on their site that they will now send out the units with the bleed screw separated from the metal block, protected in the spare parts cases on top of the unit housing.
Once more, this is reactivity and what I call customer service. On top of that, he had sent me not one, but two bleed screws, so I now have a spare.
Then came the big day, did some tests with a Hill pump (just filling the line and making use of the reliable manometer) in order to check the cutoff at 200 bar. Everything fine, but filling waaay too slowly. Checking the “mid pressure” manometer on the booster unit, it was turning between 0 and 0,8 MPa (0-8 bar or 0-116 psi), loosing all pressure between strokes which seemed not the case in the product video on YouTube.
Shot a short video, uploaded to dropbox, sent the link to Altaros and asked whether this and the slow filling were normal. One hour later (again!) I had the answer: Not normal, along with clear instructions how to fix it: two things – first check the gauge, screw it in by hand, do not over tighten (no brute force needed) and second – check the mid-pressure hose. This is the white hose interconnecting the two cylinders. It can happen that during transport, that the hose slides a tad out of the fitting, causing a leak.
While the unit is running, push the two ends of this hose vertically down in the fitting so that it can make contact with a tiny o-ring all the way down in the same fitting, which seals the hose with the cylinders. That done, the mid-pressure should build up and not fall back to 0.
If not, then – still while the unit is running – push down the blue fitting collar and slowly remove the hose. Once the hose removed, a tiny o-ring should be blown out (only way to get to it), so the best way to do this is on a white towel or similar. Just take the hose slowly completely out after the stroke. If the o-ring is not coming up with it, it will with the next stroke, be prepared, keep your hand hovering over the fitting to catch it. If ever there is no o-ring or it got lost while being blown out, don’t worry, there are two of them coming with the service kit provided with the unit and I am sure the guys at Altaros will be more than happy to send more.
Well, all that done, mine turned between 0,5 and 1,8 MPa (5-18 bar or 72-260 psi more or less).
Better already, and filling waaaaay faster, but still not at the level shown in their video.
So made another video of all working together, gauges, shop compressor, Hill pump, uploaded to Dropbox and asked what next. As I had sent the mail by midnight, the answer came in the next morning.
The point to check now was the shop compressor output. Either use the unregulated output, if present on the shop compressor, or open output valve to max possible pressure. By the way, this is clearly stated in their manual…doh… I had limited the output to 6 bar (87 psi), so I screwed the red limiter screw on my shop compressor all the way in, in order to have no more output pressure limitation.
That did the trick, some adjustments of the famous flow regulator screw Inside the Altaros unit to have a 60/40 runtime/pause ratio on the shop compressor and all is fine. With my shop compressor, switching on at 6 bar (87 psi) and off again at 8 bar (116 psi) the mid-pressure gauge now comes up to 3 MPa (30 bar – 435 psi), depending on the pressure provided by the shop compressor, which varies between the run/pause cycles. This is a good value for the shop compressor used.
Well, I am posting all this for several reasons, first is to highlight Altaros’ real brilliant customer service and reactivity which seems on par with Evgeny’s from AT who receives high praise from all the Vulcan owners.
Second is that I learned some useful stuff related to this booster unit through the exchanges with Altaros, which I will share in another post or 2 (probably written on my computer, not the mobile phone…).
Third, and I really need to highlight that: all this happened NOT due to bad design or Altaros’ errors, but due to transport and my own stupidity (shop compressor output limit, I will come back to this).
Nevertheless the guys at Altaros were always helpful and quick to answer, eliminating all issues systematically, one by one.
I wish them a lot of business with this small marvelous booster unit of theirs and wish to thank them by sharing this (positive) experience.
Ooofff, ’nuff for today…
Hoot and Knife,
Thanks for the great reviews, findings, tips, and instructions
Yep Hoot, they both agree, there’s no “Replacement for Displacement”! :rofl:
Knife :biggrinn:
:hoot:
Excellent point! Knife, your girlfriend was right…you only look stupid!!! At least your wife and her agree on something…
Hoot:
Thanks Hoot!
One other tidbit that is being left out here. Pressure is only one side of the coin. And the less important one at that. You have have to keep air volume at pressure in mind as well.
For instance, I run my up-right at 90 psi output at 11.2 cfm at said pressure. Without volume, pressure is virtually useless.
I have one buddy running a 175 psi at 2.2 or 2.5 and the fill I get in 1 hour, takes him 4 hours.
So definitely look at the CFM rating. Do not go below 5 cfm at 90 psi. To do so is just spinning your wheels. Without volume, the pressure is going to drop to almost nothing once it enters the drive piston chamber.
Think of this as the amount of Torque or Horsepower produced. a 1000cc engine at 8000 rpm cannot make the power of a 7000 cc engine at the same rpm, No where near it! LOL!!!
If you want performance, ya got to have displacement. In this case, CFM!
Knife
:hoot:
Here’s what experience has taught me…the Altaros unit will boost as fast as its potential, IF you maintain a constant 140 psi (just under the maximum 10 BAR listed) at it’s intake QD fitting. It helps if the Altaros air flow valve is wide open…which is possible, IF your compressor can keep up with the Altos unit! Otherwise, your compressor will run full time.
Second hint…refill when your fill tank is about 500 psi below where you want it. IF you wait and require a 1000 to 1500 psi, the unit will run for a much longer time!
Let’s give the machine it’s proper due…it will do the job, but you need to be mindful of it’s limits. The Altaros compression piston is an air driven slow mover, not huge in size, so keep your expectations within reasonable limits, and it will do a fine job!
The bigger the motor on your shop compressor, the larger the volume in it’s holding tank, the better the unit will operate! It can only fill as fast as your compressor’s constant air flow will allow it to fill.
I suggest, for maximum potential, and fastest fill times, you obtain a 20-30 gal compressor, minimum fill pressure of 150 psi, and a motor of as close to 2.0 hp as possible. Further, a piston compressor will refill faster than an oilless diaphragm unit, and be able to maintain a 60/40 duty cycle. If you can obtain an even more powerful compressor, all the better. Harbor Freight has some piston units in the $200-$300 price range.
A common 5 gallon shop compressor will get the job done, but will require patience on your part. Be realistic, fill times will be much slower with this approach.
Well, that’s it. your shop compressor capacity is the real key to speed and fill times from an air driven pressure booster like the Altaros.
Hoot:
Yep! No hamfisted strength required for using it. LOL
Knife
:hoot:
The black pressure release knob on the Altaros fill hose is plastic. Don’t use excessive force when closing! It’s one piece and the bottom is tapered to shut off the air. It can be damaged if you get forceful.
Hoot:
So “THAT’S” what I did wrong when adjusting!!! :confusedn: :biggrinn:
Knife
Well, just finished filling and it took as long as a shoe box. Started checking the connections and Yep— The little black mystery metal was loose again! LOL!!! :rofl:
Knife
:hoot:
When adjusting my air flow setting screw I “bottomed out” when trying to slow the air flow into the Altaros unit. Upon checking closer, I noted it was held in place by a lock nut. By loosening the lock nut I could then adjust the air flow slow enough (turning left to right-counter clockwise) to permit my compressor to shut off closer to a 60/40 compression cycle. That rascal was getting plenty hot running full time.
It took several full turns of the air flow screw to obtain results. Fortunately I found that lock nut. Just be aware of it’s existence! And, know that the air flow screw requires full turns to achieve noticeable results. You can see the pressure gauge needle hold at the high compression phase and tell that it’s taking longer to get fill air from your compressor.
Mine was set way too far out, and that was why my compressor ran non-stop. Glad I got that worked out.
Hoot:
:hoot:
Thanks Doc…
By the way, I see where the Queen of England offered to resume rule of the United States due to the mess we find ourselves in. I believe we should take her up on the offer!!!!
It tough choosing between a lunatic and a genuinely evil woman to run/ruin the U.S.
Hoot:
Haha Hoot…!
Oh by the way that was my commentary and picture on that loose fitting on the Altaros… It is some weird alien metal lol I used some knipex flat plyers to not bugger it up and to tighten it .
I wish they would of made that little black piece out of stainless or something.
But no worries bud we are totally in agreement this thing is a wonder for how small it is and what it does ! :fishinghole:
- You must be logged in to reply to this topic.
Yeah, No more of these one word wonders!
Grrrrrr!!!
I very much appreciate the time and effort of you postQ
Now, In my booklet, they give two answers as to which direction to turn that darned little air flow knob. And to top it off, my uncle confused me further. He said, Clockwise to the left HUH!!!
Do Clocks run backwards in ARK?
Dear Hoot. We Won!!! :biggrinn:
Yea!!!
Your Loving Nephew, Knife