Suggestions on a tankless compressor to drive small booster

[Reku]

I'm looking for a tankless compressor that can output ~150psi at 3-5+ cfm rated for 100% duty to drive my HII 3G-SS-20-O. This will be pumping o2/He so I'll be going slow to keep the heat down.

I'm looking for a way to filter the compressed air before it hits the booster.

Any ideas are welcome. No price limit however it needs to be reliable and be somewhat portable as I will be taking it places.

I do not want a compressor with a tank - it is a waste of space. I don't care about noise or increased maintenance from running it continuously.

I am only boosting 2L and 3L tanks. Nothing complex, no large scuba tanks.

I can find tons of compressors with tanks that will do what I need but I can't find much if any tankless compressors. If you have other suggestions or you think I'd be better served by a larger compressor than what I am thinking I am open to any discussion.

Thanks.

 

[Southside]

I would suggest reading the oxygen hacker's companion from airspeed press. There are discussions in it about filters.

Nitrox Compressor

At that link he talks about building a filter for his compressor.


On to your question about a "tankless" compressor, unless the laws of physics have changed you aren't going to find something that is capable of doing what you are looking for. You are going to need a tank in order to build pressure and keep the pressure constant. You ca=n find a small tanked compressor that is capable of doing what you want.

 

[rjack321]

I'm looking for a tankless compressor that can output ~150psi at 3-5+ cfm rated for 100% duty to drive my HII 3G-SS-20-O. This will be pumping o2/He so I'll be going slow to keep the heat down.

I'm looking for a way to filter the compressed air before it hits the booster.

Any ideas are welcome. No price limit however it needs to be reliable and be somewhat portable as I will be taking it places.

I do not want a compressor with a tank - it is a waste of space. I don't care about noise or increased maintenance from running it continuously.

I am only boosting 2L and 3L tanks. Nothing complex, no large scuba tanks.

I can find tons of compressors with tanks that will do what I need but I can't find much if any tankless compressors. If you have other suggestions or you think I'd be better served by a larger compressor than what I am thinking I am open to any discussion.

Thanks.

This is because the compressor you've specified does not exist. tankless, 150psi+ output, 100% duty cycle, 5+ cfm (which is not really enough for that booster btw), portable… They all have receiving tanks because that's where water condenses, the tank buffers the flow, and slightly moderates the duty cycle so the compressor can vent a little heat. Sorry to say but the tank is an essential element of any shop booster.

Your options are:
1) to boost using a set of doubles full of nice dry scuba air and a reg set at ~155psi IP via BC whip.

2) a small oil-less compressor like this dewalt. Try not to run for extended periods of time in hot weather or you'll kill it. https://www.lowes.com/pd/dewalt-4-5-gallon-portable-electric-horizontal-air-compressor/1036715
With that booster and this compressor you will be running 75-85% duty cycle which is high. So filling more than CCR tanks will kill the booster and the compressor very fast.

You should add an air drier with at least some silica desiccant like this one:
https://www.amazon.com/Cleaner-Dryer-Campbell-Hausfeld-PA208503AV/dp/B0009KN9T0/

The smaller the receiving tank on the compressor (and the longer you run it so the hotter the outlet gas) the faster the desiccant will saturate.

 

[runsongas]

you can get a rotary screw compressor, but they also require 230v power, are not compact/portable, and cost 3k+.

First Air FAS4 5-HP Tankless Rotary Screw Air Compressor 230V 1-Phase 150PSI

 

[tbone1004]

Problem #1-you can't get 5cfm out of a portable compressor. 1hp is really about as much as you can put on a normal wall outlet, and that will be about 2cfm at high pressure, up to about 40 when it's at low pressure.
Problem #2-150psi is very rare in smaller compressors because no air tools run on pressures that high. 120-125 is about as high as you are going to find. Not sure what the boost ratio of that booster is, but I know with my AG30 I'm limited to about 3800psi when filling. I'm certainly OK with that when travelling. If I needed to run my bank bottles all the way up for whatever reason, I would need a higher pressure compressor, but 3800 is enough.

Problem #3-this is easy. Just remove the tank and chuck it. On my booster box, I used a California Air Tools compressor but it was cheaper to buy the whole thing. I removed the tank and plumbed everything in, super easy. Now, the problem. Any "big" compressor in terms of volume is going to have a capacitor, so you have to find somewhere to put that for power, then you have to figure out filtration, mounting the pressure shutoff switch, etc. Filtration is critical with these boosters, both from water, and particulate or you'll murder the drive gas section.

 

[Reku]

Alright I've got choices to make. Thanks guys

 

[happy-diver]

That setup is gorgeous man

Do you have time to be one of my heroes?

 

[tbone1004]

That setup is gorgeous man

Do you have time to be one of my heroes?

thank you, I am quite pleased with it

 

[happy-diver]

Geez! I'm certainly contemplating borrowing your design.

I've only managed to stuff this one in a plastic box, although it is bolted in nice and straight now
although one morning filling tanks with drive gas and mixing the next is really staining my brain.

Been attempting to rebuild this electric one for five years, should knuckle down and get it done

 

[Reku]

So I've inherited an old Cornelius 130r1500. I should be able to regulate the pressure on this down to ~130 psi to drive my booster. I guess my problem solved itself.

From what I've read these compressors are slow but fairly robust. Which is fine by me I just need it to slowly drive the booster to keep things cool.

I still need to figure out filtration. I suspect from reading I'll be spending around 1k on filtration or more - unless anyone has any other ideas? I'm looking to output Grade E at a minimum or OCA if the price isn't insane.

Is there a downside to using a normal scuba 1st stage to regulate the pressure down to ~130 psi for the booster?

All of the boosters and fill stations I've used in the past have used dedicated shop compressors or from the bank to feed the booster and not a regulated scuba compressor.