Need Info on Compressors

[Dan Gibson]

Then your going to have to fill them on site. At a minimum, your going to spend about 2 hrs filling 6 tanks. That is if you get a compressor that allows you to fill a bunch of tanks in a row. Some of the smaller compressors need a break between fills.

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

 

[captain]

If you are serious about diving and you feel sure it is not something that you might quit doing in a year or two. get the compressor, you won't be sorry.

Captain

 

[oxyhacker]

Filter life varies wildly according to temperature (though not humidity) - most compressors come with charts that let you figure out how many fills you can do. Bauer tends to use slightly (for the USA) optimistic so you will probably be getting less than 40 fills in real life. The best low-bucks way to monitor filter life is with a cheap "eyeball" moisture/CO detector such as Aqua Environment sells.

Ditto draining. You can probably get away with draining every 1/2 hour/one tankful, but most operators like to play it safe and do it sooner rather than later since its easy to wipe out the filter by letting it go too long.
The need to drain is directly proportional to the amount of water in the air - a typical hot muggy Florida summer day will produce huge amounts of condenseate compared to the same day in NE (or Germany!).

Remember too that the smaller/cheaper compressors are not rated for continuous duty are supposed to be allowed to rest every 1-4 tanksfulls. Bauer does make a deluxe small compressor, the Oceanus, which outputs a bit more than the Junior, and is (best I can recall) rated for continuous duty, but it's significantly more money.

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?



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.

 

[legend15]

Hi,

Im on this site to see if people are interested in buying compressors for diving use, i see by your message that you are looking to buy one?what price region are you looking to be paying? Im from england but can get in touch with people in the staes to provide you with the breathing equipment needed.

 

[quimby]

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

Sorry, nuerological flatulus(brain fart). Not filling that much at a time now, just filling during the week for weekends now and getting tired of fill rate. I used to have a shop and am used to a 19cfm Rix so a 3 kills me. Should have a 6 later this year.
The CB is for continuous blending, basically adding gas to the compressor intake at a fixed rate for pumping nitrox and trimix. Running in the intake allows you to empty the storage bottles and as long as the O2 levels are kept reasonable its a match with the rix being oilfree

 

[The Curly One]

The Aqua-Environement Co / Moisture veiw monitors are cheap insurance and a good investment on any portable breathing air compressor in my opinion.
Filter life does vary quite a bit on most portable compressors. The water separators and purifier on the ALKIN W32 Mariner weighs about 75 lbs. It will last a long time but that is a lot of weight to be carrying around. The whole W31 ALKIN portable compressor only weighs 119 lbs. You should get 40+ tanks from a filter with most portables. More if you are in a cool dry climate. With the larger stationary shop compressors you will get much more like 300 to 500 tanks and more because of the larger filtration. Portable and shop compressors are really not designed for the same purpose. We can sell them with any size filtration you want but then they are not really portable and the larger filters take much longer to fill and pressurise for a small CFM unit.
I also agree that if you dive quite a bit and you are in it for several years you will be glad you got a compressor.
I recommend that you purchase a good compressor for the simple reason that the resale value is so much better. If you buy a good compressor and take care of it you should be able to get most all of your money back if you ever sell it. That makes the cost of ownership almost nothing. A good compressor is rebuildable and the cheaper ones are basically a disposable unit.
A good quality compressor runs at low RPM to stay cool and quiet and uses Stainless Steel for strenght and corrosion resistance.
The 2 best features of the ALKIN W31 portable is that you can run it up to 8 hours non stop if needed and it is very quiet. The Bauer compressor that looks like the Jr. but puts out about 4.9 CFM and has the oil pump (Oceanus?) is another good portable compressor. The Rix units have some disadvantages but they may be a good choice for some people due to the oiless design.
I beleive that if the compressor is turning over 1400 RPM or so that it should have an oil pump. Not so much for lubrication but for cooling of the pistons or be limited to very short running times. RPM and heat is not good for anything.
To answer someones question. Yes, Genesis does have the ALKIN W31 model as do several others here. He has added a pressure mainining valve and he also uses a "eyeball" style moisture / Co Monitor. Just my opinions. The Curly One

 

[Uncle Pug]

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 don't think you would want the RIX SA3 for portable use filling 4-6 tanks at a time... or any other small compressor for that matter... unless you didn't mind hearing a small gasoline engine disturbing the peace for hours at a time. Think of camping next to someone running a lawnmower for the fun of it.

If you are going to go portable, that most likely means gas powered, then cutting the running time in half will be important IMO.

As has already been mentioned a good quality compressor will maintain its value better than a cheaper one. Even at that I have already (in three years) amortized out my SA6 pumping nitrox.

If I were you I would think about not only getting a portable (gas powered) but also have an electric motor that you can put on it for use at home.

Vance: I have 175 hours of pumping nitrox on my current set of third stage rings... but then I also have an auxilary fan helping to keep things cool.

 

[captain]

I bought a U S Divers Cyclone compressor made by Luchard of France in 1968. Other than changing oil and fillters and cleaning the valves I have never rebuilt it. It still pumps up a tank in the same time as when it was new. It is cast iron and runs at 1500 rpm with a 5 HP gas engine. I have no idea how many hours it has but it has been one damm good compressor.

Captain

 

[erikharwell]

this may not be a good idea but what about a hp storage bottle and a haskel pump. it would take a whole lot less time to fill the tanks on the trip. I dont know what one would cost and if this would be pratical, but it might be another option. also what about leasing the compressor.

 

[Bob3]

Depending on where you're planning on diving, a hookah may be an option you'd want to look at.
When we're out commercial harvesting there's no room for a pile of tanks, & a gallon of gasoline can keep a couple people on the bottom all day long.

I bought a U S Divers Cyclone compressor made by Luchard of France in 1968.

Dang, here I though I had the only one in the US.