What filter cartridges should I use? Two 32" stacks for a 6 CFM compressor

[tbone1004]

@tmassey if you want to think of it as internal compressor filter and hyperfilter than I'd go with what @rjack321 said. You'll have more frequent replacement of the "internal" filter as it gets wet, but should be able to go quite a while with the second one, pretty much until it makes you feel like you need to change it.

 

[tmassey]

The problem with the LF humidity strips is 1) you cant see them in real time use and 2) they are activated at 40% RH which is way too wet. Probably not a big deal if the only the first one is partially changing. But for cold water you want that 2nd one totally blue blue. And a final RH in the 10-20% range.

The second filter has never been anything but 100% blue, even today. The first filter has never been, either, until this spring, where it was 100% tan. So it gets replaced no question.

It's not so much that I *want* to think of it as a hyperfilter, but that's really what it is. It's a bunch of add-on stuff attached to a board that I feed the output of the compressor into. The board was originally designed and built when I was going to use an MCH-6, which *needed* (or, at least, could really use) some help. Then I got this compressor before I even filled a single tank with the MCH-6, and it already has a reasonable coalescer and large filter stack nicely integrated into it, and I'd be a fool to tear it apart. Really, the entire filter board is completely superfluous, but I have it, so I use it. So it's a hyperfilter!

PFU-150 High Pressure Compressors - Fill Stations - For Fire Service and Scuba Diving - Poseidon Air Systems - Colchester Vermont

Just placed the order for a 13x/AC filter for the compressor. I could still disconnect the filter board tomorrow and have at *least* Grade E, if not OCA, and I have CO monitoring to cover the lack of hopcalite.

It really is a nice compressor -- except for the drains!

Thank you all for your help. I'd certainly love to hear some other perspectives as well! But I've ordered the cartridge...

 

[rjack321]

dual filters act as much like a hyperfilter as any marketed hyperfilter - assuming you change them. You dont have to believe me either, @nadwidny runs a gas analysis lab in Canada.

 

[nadwidny]

dual filters act as much like a hyperfilter as any marketed hyperfilter - assuming you change them. You dont have to believe me either, @nadwidny runs a gas analysis lab in Canada.

With proper maintenance, most single filters give the same results as a hyperfilter.

 

[TrimixToo]

My approach to this was simple. I called Filter Techs, told them what I had, asked them what to get, and ordered those filters. (This is, after all, what they do.) My compressor has never failed an OCA test.

 

[NAM001]

i WOULD DEDCATE THE FIRST STAGE TO X-13. that will prep the air (lowest dew point) for the max effect for the followup filtering for co co2 and hydrocarbons. I would continue to use both units to max the dwell time. the moisture part of the filter reportedly us consumed first so having a dedicated unit for x13 lets you max out the other filter chemicals perspective use. Not knowing the environment you are p;umping in I would guess if the second had 10-20% monoxicon and the rest carbon you will be set.

 

[TrimixToo]

i WOULD DEDCATE THE FIRST STAGE TO X-13. that will prep the air (lowest dew point) for the max effect for the followup filtering for co co2 and hydrocarbons. I would continue to use both units to max the dwell time. the moisture part of the filter reportedly us consumed first so having a dedicated unit for x13 lets you max out the other filter chemicals perspective use. Not knowing the environment you are p;umping in I would guess if the second had 10-20% monoxicon and the rest carbon you will be set.

I think you mean 13X. (X-13 was an early VTOL jet aircraft.) And, I agree with you. But I'd ask Filter Techs first to confirm my bias.

 

[NAM001]

I think you mean 13X. (X-13 was an early VTOL jet aircraft.) And, I agree with you. But I'd ask Filter Techs first to confirm my bias.

you are right. at least the message got across.

 

[NAM001]

nadwindy said this

With proper maintenance, most single filters give the same results as a hyperfilter.

He makes a good point.... Long ago I was in a similar discussion on SB regarding the need for Hype E filtration for notrox. Many said they put on a grade E filter and sent in an air sample and it far passes the Hyp E standards. You buy a filter that is good for 40k cuft and it is made to provide grade E air for the ;LIFETIME of the filter in this case 40k cuft. I sent a sample in once and got a hyp E result after a couple of years us use. I at the time was using a Rix S6. I had pumped no where near the cuft the filter was made for. I would guess they could sell the same filter as a hyp E but its life would be advertised at 1/2 the cuft as advertized for the grade Es standard. MARKETING !!!!

Its my opinion but you can never have too much filtering. It doesnt cost any more as upleep goes. Yes there is a point of no return, like anything. The more you add the more dwell time you get and the better the filter works If you had a five stage then the last filter would probably last for years and you only change the front ones. Moisture is a killer of chem filters so the best water removal system on the front end the better. Mechanical and min one dedicated 13X filter. 13x is cheap and yeilds so much return in the end.

 

[tbone1004]

@KWS there is some science in there outside of the hyper filters though. When you buy something that is sized for 40k cf, it's also sized for a BIG compressor. With a small compressor like the Rix, the dwell time is going to be twice as long as a 12cfm compressor that it was likely designed for.
Also of note, the hyperfilters are to get rid of hydrocarbons, and the Rix doesn't generate them. An oiled compressor absolutely will and that has to be taken out. Filtration for a Rix is only going to take out whatever you put into it. Water, residual CO/CO2 from the environment, and any particulate that the pre-filter doesn't take out. It's not going to have any oil which is a large amount of what the hyperfilters are aiming to get rid of. Good coalescers will get damn near all of it out though since it will knock out with the water.