Need Info on Compressors

[got4boyz]

I have been looking at Bauer and Airetex, both in the 3 to 3 1/2 cfm range both around 100 pounds, both have gas and electric models. The gas are around $300.00 more than electric. Airetex is less than Bauer, both are in the 3k range.

I agree with Mike in that you can buy alot of tanks and air for that money, and then also agree with Captain about the freedom. With all the dive shops in my area closing it is getting hard to get air fills and cramps the diving style. Which is why I am looking.

Mike

Hi VW Mike! My only reason for wanting a compressor is for convenience since many of the places I want to dive are hours from any air source!

WV Mike are you leaning towards one of these vs the other? I have no idea which would be the better buy.

NWdiver - I appreciate your info. Any idea how much a smaller Rix would cost. It sounds like yours is a big bigger than I'm interested in. (Well, than I dare spend on, that is. I'm interested in bigger that fills faster, but there a budget to consider! LOL)

I've called Rix twice and keep having to leave messages so I have no idea what their units cost.

Captain, I'm thinking I will want a gas powered, so if I decide to just take my Suburban instead of the motor home I can still power the compressor. Besides, the gas powered seem to have a slightly faster fill rate.

Thanks again for your replies, any further info on compressor preferences would be appreciated.

 

[Boogie711]

Bear in mind your air intake if you're operating with a gas engine. And Beth - you're going to be looking at 3K minimum. You might be able to find one that needs maintenance et al for a few dollars less, but unless you know what you're doing, I wouldn't mess with it.

Also bear in mind the costs associated with filtering and maintenance. It's not just as simple as plugging in a machine and going - you need to keep an eye on your filters so you don't pack CO or any other nasties into your breathing air. You need to monitor condensation so the moisture doesn't get into the tanks. And if you want to do anything other than plain old air, I'd consider getting a blender's course, which is going to cost a few hundred dollars as well.

All of a sudden, the cost of 20 AL80's doesn't look so bad, does it? Especially considering you can probably swing a bulk deal if you buy an entire batch like that.

 

[DivemasterSteve]

All of a sudden, the cost of 20 AL80's doesn't look so bad, does it? Especially considering you can probably swing a bulk deal if you buy an entire batch like that.

i dont know for sure but i would guess the cost of 20+ tanks is not as big a problem as the weight and space to carry that many tanks are. i know it would be that way for me.

steve

 

[quimby]

NWdiver - I appreciate your info. Any idea how much a smaller Rix would cost. It sounds like yours is a big bigger than I'm interested in. (Well, than I dare spend on, that is. I'm interested in bigger that fills faster, but there a budget to consider! LOL)

I have a sa 3 and if Im not mistaken new its around 3500 and the sa6 is 5500. Uncle pug ran the numbers on here a while back but beyond the search limits. If I were filling 20 bottles at a shot with a 3cfm I'd consider it a career and would be looking for a sa6. I am since the 3 was only a interim answer and CB was also a requirement and soon to have the 6
Might want to look at alkin (cheaper and good reviews) if not really going CB, but quite a few rigs doing a Hyperfilter and CB and or PP blend

There's one that I've heard real good things about but I can't remember the name. Genesis baught one of them

Genesis owns one of the Airtex/Alkin W31s.

 

[oxyhacker]

Unless you want to spend a lot of money, the Coltri MCH6 (also sold as the MaxAir 35) and the Bauer Junior, for $2500 to $3600 new, $800-2500 used, are going to be your best bets. The general feeling is that the Bauer is well worth the extra money. MaxAir used to have an exclusive on the Coltri here, but now they seem to be coming through under the Coltri label, for quite a bit less than MaxAir gets. And Poseidon sells a version of the Bauer for a bit less than Bauer gets. I wouldn't fool around with the Rix, much as I love them, unless you are mechnically inclined - they are noisy, need greasing with special grease every 25 hours, the HP rings must be replaced every 50-150 hours, they cost about $1000 more than an equivilent Coltri or Bauer, and need about $400 worth of additional filtration to be really usable. The Alkin is interesting, but is quite a bit bigger.

You sound like you want something that could be more or less built in to the camper. If you want to do that, you'll need an installation similar to a yacht installation, with automatic drains, and cutoffs. This can easily double or triple the base price and are often problematic for cooling. Since your generator is probably marginal for this purpose, your best bet is probably a small gas powered unit which you can pull out and set up some distance from the RV.

Running a small compressor is a lot of responsibility - you need to drain the separator(s) every 15 minutes, and replace the filter cartridge every 5-30 tankfuls. If you don't, the compressor outputs dangerously contaminated air. All these compressors pump less air than the ratings would suggest, so plan on them taking 1/2 an hour or so for each 80 filled. But it sure is nice to have all the air you need on hand, and be able to to just top up a partially used tank.

 

[quimby]

they are noisy, need greasing with special grease every 25 hours, the HP rings must be replaced every 50-150 hours, they cost about $1000 more than an equivilent Coltri or Bauer, and need about $400 worth of additional filtration to be really usable. The Alkin is interesting, but is quite a bit bigger.

Not to debate the rix's +or- but noise is really no worse than any other compressor and that means not for the faint of heart. The greasing is a none issue for the 30seconds that takes and the filtering is actually moisture removal not for exerciseing the evil hydrocarbon devils.
The rings go quite a bit farther with a little extra cooling, ie a real blower across the unit and although I dont have exact numbers I am over 300hrs and can still run to pressure shutdown.
But for all the niceties of a compressor, your dead on with paying attention to heat, filters and expenses, and is really a commitment that requires focus, no cutting corners unless your Cal.................
One other point, considering recent events is CO monitoring and worth the time to check recent posts on that.

 

[Dan Gibson]

That would be the Alkin and they are pretty nice. Electric is great if you don't take it mobile since they are the quietest out there. The gas version is just as noisy.

Bruce Dodson at Airetex is the person to contact. There are also several other dealers popping up in the states.

www.airetex.com

I think you can get a small compressor...3 cu ft/min or so for around $3,000

Max air, Bauer and some others make some small ones.

There's one that I've heard real good things about but I can't remember the name. Genesis baught one of them.

 

[got4boyz]

Also bear in mind the costs associated with filtering and maintenance. It's not just as simple as plugging in a machine and going - you need to keep an eye on your filters so you don't pack CO or any other nasties into your breathing air. You need to monitor condensation so the moisture doesn't get into the tanks. And if you want to do anything other than plain old air, I'd consider getting a blender's course, which is going to cost a few hundred dollars as well.

Thanks Boogie, that's a great point so I have guesstimated some figures to get an idea of the cost including filters, oil, etc. I will only be condensing air. How do you know when your filters needs replaced? Baur said it was good for 40 fills. They said I would only have to drain it after each tank fill and change the oil once a year.

All of a sudden, the cost of 20 AL80's doesn't look so bad, does it? Especially considering you can probably swing a bulk deal if you buy an entire batch like that.

Well let's see, I decided to compare the cost of the two.

Say we go diving 8 times a year for 2 days/2 tank dives. That's 32 tanks each trip times 6 people for a total of 192 tank fills a year.

If I go with the compressor I'll still need 6 tanks :

6 Tanks 810.00
Compressor 3,300.00
Filters 175.00
Oil 30.00
Fuel 50.00

Total 4,365.00

If I buy 24 tanks then these are the numbers:

Tanks 2,880.00
Refills 960.00
Yearly Insp 240.00

Total 4,080.00

Hydro every 5 years $600.00.

That's only a $300 difference unless I'm missing something somewhere!

Beside as DivemasterSteve pointed out, it's the bulk of carrying that many tanks that's the real problem. I have a lot of space in my motorhome, but not that much! LOL

Anyway, unless they are really too much of a pain a compressor is looking better all of the time. And hopefully we'd dive more often if it was more convenient.

 

[got4boyz]

I have a sa 3 and if Im not mistaken new its around 3500 and the sa6 is 5500. Uncle pug ran the numbers on here a while back but beyond the search limits. If I were filling 20 bottles at a shot with a 3cfm I'd consider it a career and would be looking for a sa6.

Thanks quimby, I would want the SA3. I wouldn't be filling 20 bottles at a time. I would need 24 tanks IF I didn't have a compressor. I'd only be filling 4 - 6 at a time.

I am since the 3 was only a interim answer and CB was also a requirement and soon to have the 6

You've confused me a bit here! Does "I am" mean you are filling 20 bottles at a time? What is CB? and are you planning on buying a 6 soon? If so, do you want to get rid of your 3? LOL

 

[got4boyz]

Unless you want to spend a lot of money, the Coltri MCH6 (also sold as the MaxAir 35) and the Bauer Junior, for $2500 to $3600 new, $800-2500 used, are going to be your best bets. The general feeling is that the Bauer is well worth the extra money. MaxAir used to have an exclusive on the Coltri here, but now they seem to be coming through under the Coltri label, for quite a bit less than MaxAir gets. And Poseidon sells a version of the Bauer for a bit less than Bauer gets. I wouldn't fool around with the Rix, much as I love them, unless you are mechnically inclined - they are noisy, need greasing with special grease every 25 hours, the HP rings must be replaced every 50-150 hours, they cost about $1000 more than an equivilent Coltri or Bauer, and need about $400 worth of additional filtration to be really usable. The Alkin is interesting, but is quite a bit bigger.

Thanks for all the above great info. Decisions, decisions, decisions. I definitely don't want to spend a lot of money.

You sound like you want something that could be more or less built in to the camper.

No, not built in because I might want to take my Suburban sometime or a friends' boat so something, so I'm deciding portable would be better, so I'm thinking I definitely want a gas one unless there are convincing reasons not too!

Since your generator is probably marginal for this purpose, your best bet is probably a small gas powered unit which you can pull out and set up some distance from the RV.

I agree. I'm thinking my generator might not even cut it at all according to Bauer's specs.

Running a small compressor is a lot of responsibility - you need to drain the separator(s) every 15 minutes, and replace the filter cartridge every 5-30 tankfuls..

I was told by Bauer that I only had to drain them between tanks and the filter would last for 40 tanks. How do you know when it needs to be changed?

All these compressors pump less air than the ratings would suggest, so plan on them taking 1/2 an hour or so for each 80 filled. But it sure is nice to have all the air you need on hand, and be able to to just top up a partially used tank.

Well I didn't like hearing that. I wasn't liking the 20 minutes I thought it would take to fill. Adding 10 more minutes to 6 tanks is an extra hour! Too bad I can't afford a faster one.

Anyway, thanks all so much for all of your great info.