Large Booster (ag30,ag15/30 etc) vs Coltri mch6 3.5G omnibooster

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Reku

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My previous 2.7cfm compressor is dead with no chance of spare parts. It was about 50+ years old. It was dying before I got it. It served me well for a year.

I'm thinking about picking up an mch6 gas powered unit because it has spare parts available and electrical service here is questionable. It helps that it's currently on sale for $2500. Also the coltri compressors are rated for helium, 40% nitrox and other technical gases without voiding the warranty according to the manual.

The sole purpose will be to economically scavenge helium to 0 psi from industrial bottles and leftover trimix from various other tanks. I have so many tanks that are partially full I will break even immediately on compressor cost. However I don't want to kill the compressor. I've read about the care requirements for coltri compressors and the submerged 4th stage in the mch6.

I know the mch6 can't handle banks - I won't be scavenging for longer than it takes to fill a 130 or until the compressor needs a break and then rinse repeat.

I've looked into AG30s / AG15/30s and AG75s for this but the cost and drive gas required are immense. As far as drive gas is concerned I'm currently boosting o2 with an HII 3G-SS-20-O and it works great for the single task it has - I don't need to empty the o2 bottles as o2 is extremely cheap for me. Also as stated above electrical is an issue so having a large enough LP compressor for anything more than a mini booster is problematic...

I am concerned about gas fumes from a gas powered compressor even outside - has anyone ever put an extended remote exhaust onto a honda 160 5.5hp motor before? Assuming the seal on the omnibooster is tight I shouldn't have an issue with fumes contaminating the fills but you can never be too careful. A fume extractor is also an option. I test for contaminated gas every time I fill regardless of type of compressor.

Other unit suggestions would work as well - I just saw that it was on sale, the warranty allows for what I want and thought I may as well look into it.

Other solutions to my issue are also acceptable.

Considering the sale costs of the mch6 vs other options - I feel like I should just jump on this while it lasts.

Thoughts?
 

michael-fisch

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As the inventer of the Omnibooster, naturally I'm biased and would say go for it. Eventually you'll also need access to a booster for HP O2. My thoughts on a HP booster for O2 are running towards an electric Masterline for @8.5K. Getting a big old 100cfm LP compressor with decent filtration and a Haskel AG15/30, installing the electrical wiring and the pipeing, upgrading the Haskel checkvalves etc wouldn't end up being much cheaper for me.

Michael
 
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Reku

Reku

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As the inventer of the Omnibooster, naturally I'm biased and would say go for it. Eventually you'll also need access to a booster for HP O2. My thoughts on a HP booster for O2 are running towards an electric Masterline for @8.5K. Getting a big old 100cfm LP compressor with decent filtration and a Haskel AG15/30, installing the electrical wiring and the pipeing, upgrading the Haskel checkvalves etc wouldn't end up being much cheaper for me.

Michael

I may have to rethink this gas engine idea - apparently I need to keep sound down to 63db at the property line. With the compressor running at 80db-83db and neighbors being about 20-30ft away that doesn't leave much to get the sound levels down.

Has anyone had issues with neighbors and compressor noise?


Regarding hp o2:

At the moment instead of bringing 3000+ psi of o2 I just bring whatever I can transfill and boost a bit more into an 80....which is ends up being around 60cf. If I need more I just bring another 80 with as much o2 as I can get into it.

I'm running lp14s on my CCRs and it's working well.

For now having half full tanks is working fine and I don't mind the extra tanks.
 

tbone1004

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@Reku
replacing mechanical fan with electric will reduce noise
replacing the intake filter with a larger one like one from Solberg designed to help silence compressors will help as well
replacing the intake filter and exhaust muffler on the motor will help *though make it bigger and less portable*

You could also get an electric motor and run a generator to power it. More expensive, but generators are typically much quieter and you can separate them.
 

Chris H

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I have an AG30. If you are trying to scavenge every last molecule of Helium, you want a different booster.
 

rcontrera

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Just a quick note on that MCH6.. The $2500 one is a standard gasoline model. We bought too many and still have quite a few waiting to be sold. Normally, that wouldn't be a problem but the gas engine has changed on the 2020 units. Electric and 2020 gas units are still on sale for $2700 base price
 
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Reku

Reku

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Just a quick note on that MCH6.. The $2500 one is a standard gasoline model. We bought too many and still have quite a few waiting to be sold. Normally, that wouldn't be a problem but the gas engine has changed on the 2020 units. Electric and 2020 gas units are still on sale for $2700 base price

Is the difference in engine large enough in that I should buy a 2020 model?
 

rcontrera

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Basically cosmetic change in the Honda line.
 

Noomi SY

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Basically cosmetic change in the Honda line.
I could be wrong, but it's more than cosmetic. They swapped the Honda GX for a Honda GP. Commercial duty for light duty.
 
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