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This is the ambient CO from the Honda being sucked back at that same positioning of the compressor at 11 PPM.
Using hose for snorkle intake is useless, no wind and with the proximity to a building......ambient CO do get suck in
This is a worse positioning, near my own compressor, has wall on back of the tested Mariner and on its right side my building.
The high power yellow blower is ON to help flow exhaust air away form the Honda, but no-can't-do given the building surrounding it.
Notice air intake for tested Mariner is taken from near the yellow blower output which has 4 of big PVC tube all the way to the roof for fresher air.......still no-can't-do.
Heat testing of MS 13X can tell an expired MS but can not tell a semi saturated MS which still can produce heat. It can take 23% of its weight in water, so 10% semi-saturated MS is still has good heat energy.
Buy the 10/20/30 humidiy plug, not the one I use 20/40/60. Its more accurate and you have pre-warning at 10% towards 20%.
Bauer PMV will not last long when one does extended filter service life beyond the table.
The MS will generate clay like mud and the activated carbon will generate sulphuric acid. The Bauer PMV is aluminum. It uses its internal boring ( hole ) as a seal for its o-ring. When the PMV is corroded internally you will loose function of the PMV ( it will be semi open mode ) no matter if you get a newest repair kit , it will not hold proper pressure the way it should be.
The American Bauer uses Aqua Environment PMV, they call it priority valve or back pressure valve. Its design is more "forgiving" towards filter life abuse in some ways than a European Bauer PMV as found on P21 or P31 right side.
This PMV attached is what this tested Mariner 200 has and look at what happen to its internal.
Merely a bit of surface finish damage as marked in green, that PMV will not hold pressure properly. Still useable but not reccomended to keep it. A complete new one is what one must buy for Bauer PMV in such condition. US$300 is expected.
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Typical condition of the PMV when abused too long, 2 photos.
This is what happen to a saturated MS. 2 photos. I keep ALL of my expired P41 filter cartridge since day 1. I want to allow ambient water vapor to saturate it slowly and see what happen to it if I lay it around in my office floor. See the photos.
Now, in a P41, the micro bubble clay you see on the filter cartridges is the OUTPUT portion of the filter cartridge. Unlike a P21 filter cartridge which its side holes are air INPUT and middle nipple as air OUTPUT. The P41 is long so no need fancy u-turn for the air to be routed like in a small P21 cartridge to increase dwell time. So in a P41 the middle nipple is INPUT.
Bauer uses a foam pad as dirt trap and liquid form oil trap, supposedly it is a 20 micron or so and all other filter cartridges using cloth like pad ( like ur P21 ) won't be of any finer filtration. Unless you get another filter tower with 2 or 0.5 micron special particulate filter.
Can you imagine the dust generated by this micro bubble clay if it gets into our lung and it will go into our lung if one saturate the MS in a real air-fill scenario like my test. Take a look at the safety sheet of MS 13X, its dust is considered dangerous and Ian once told me that in a medical compression chamber application a special non cancer kind of molecular sieve is available.
Ok you got a 1st stage regulator with sinetered filter, perhaps that may catch this micro dust or it may not because as far as I know 1st stage regulator sintered filter is not even as tight as 10 micron. In a continuos high level Nitrox blending scenario , this kind of dust can promote explosion under all the right circumstances. Ian would know better for such disaster possibility and may probably tell you stories we all want to hear about.
I have a Swagelok 0.5 micron particle filter but I have not used install it yet and I also got a 30 micron particulate filter with sintered metal filter I wish to place it upstream of the 0.5 micron because 0.5 micron will clog very fast for sure. These are supposed to be installed with the dewpoint electronic sensor I wanted to install on my own Jakarta based Mariner 200 but still pending Bali's fun experimentation.
I am going to do as you and Iain Middlebrook suggest and add the following:
* P21 output
* Check valve (to keep pressure in tower when P21 is bled). GOOD, PMV even though acts like a check valve but it is a leaker, mild leaker
* 33-inch tower (for main filtration - filled with 13X MS and AC) Better yet get MS+AC+Hopcalite X65247 LF
* Bleed valve (for bleeding when I change the tower filter). Sure, must use this.
* Moisture visual indicator 20/40/60 (to indicate earlier change of filter as required - I thought it better here to keep ensure the Hopcalite is always dry). CHANGE TO 10/20/30% TYPE
* Hopcalite in Undersea filter housing (to remove ambient CO). LFX65247 cost only extra US$5 as a hopcalite version over a non hopcalite one, why bother using your UnderSea filter housing and add resistance to the air path, but if you want this should be OK as Hopcalite works removing CO based on percentage.
* PMV set to 150 bar (to increase dwell time in tower). YEP, this is the PMV after the 33" tower.
* Check valve (currently there already to stop Oxygen travelling to filters when PP filling through manifold).
There is one little trick if you want a "$lut" 33" filter tower.
Get a Bauer P2 ( USA name , P61 Europe name). Get the special adaptor to allow the Bauer to use LF ( or Mako ) filter cartridge. So you have the best of US and German supply of filter cartridges. For Bauer you get the 58827 filter cartridge, which is the same spec as X65247 which has hopcalite or you can get Mako PD-1803. Bauer filter cartidge has MALE nipple, others has FEMALE port. A US type 33" tower with male NIPPLE can take Mako or LF cartridge but can't take BAUER one. Bauer one modded with the special adaptor ( 1 minute job with proper extension rod to install it ) can do both........so its a "$lut" hehheeh. The LF or Mako filter cartridge will have a bit of air space on its outer diameter when you placed it in a Bauer P2, but thats OK.
I so happened to be lucky and get a special Japanese market Bauer P2 , it is thicker by 0.25" than normal 4" OD P2 because of special requirement in Japan.
Good luck shopping and rigging Jason.
Sorry I dont know anything about Helium....so me cant help u there.
Hmmm, that CO is a problem with levels that high, at 11ppm or 45ppm maybe you need to add a single hopcalite only filter in there to reduce the levels. From what Ian has been telling me, Hopcalite will last for a long time but the gas must be completely dry for it to work. Maybe you best bet is to set up an exhaust snorkel for her and an intake snorkel that are both large pipe and are in opposite directions. If she is getting you to look at her system, she must be concerned. Maybe you could rig up a log book and counter for her staff, so they change the filters on a regular schedule. By the look of the damage, it looks like it will cost her more in the long run to not have the filters changed regularly, plus it could be deadly for her customers and staff.
I'm glad that you approve of the parts that I'm adding. All the parts that I will be getting will be the AE ones except the filter tower. I have checked my Bauer PMV and it is in very good condition. The P21 is fitted with a repackable stainless steel filter Repackable Filters , so I am not using Bauer cartridges. The only disadvantage of this one is that it only passes the gas through one way, and avoids the U-turn, so the dwell time is less. This was why I added the Undersea filter in the first place, but without a PMV downstream, it was a useless effort. Soon, it will all be fixed.
I was thinking that I would get the LF 33-inch tower, because it is a lot less in cost than the Bauer equivalent. Then I would get two cartridges and maybe a refillable one too. I can buy 13x MS, AC and HOP here in Australia.
I will also add another inline filter with 2 micron as suggested by Mike Casey at LF and may look at a .5 micron, but I would have to get one with a good Cv so not to stagnate the airflow.
Today, I fitted some large diameter pipe to the intake of the compressor. The intake is only 20mm, but the pipe I added has an ID of 55mm. There is a formula that roughly says that if you double the ID, then the internal resistance is decreased by 16x for each double, so I approximate that I have reduced it by roughly 20x. I think the high CO2 should be much less now.
I like the look of those CO meters you have, where did you buy them from and how much did they cost? I might have to get myself one of those.
Not too worried about the Helium, it comes from a commercial gas supplier, I transfill it into my own dedicated banks and then boost the rest. The last 10 bar, I run through the input of the compressor using a balloon system, which only takes about 4 minutes. Then I send the bottles back to the supplier. Balloon System.jpg
Sounds good. Yes, I seen the LF 2 micron filter element and stand alone tower. Looks nice. The key to fine particulate filtration is total surface area of the filter element and hence you get total dirt holding capacity in grams. I use two micron filter a lot in my work with diesel fuel for generators.
This particulate is real physical filter, not chemical like our compressor MS+AC+HP, so they do get clogged
Yes Hopcalite do not get saturated like MS or AC since it is not adsorber, it is a converter aka catalyst but need like -48C Dewpoint to reall work well.
If you do your own packing, make sure the AC you get is coconut shell one and not from coal. The common AC is for liquid phase and we want gas phase one. The gas phase one is mainly using coconut shell , it has more pores size suitable for gas phase, the kind we need for gas purification. In any adsorber, pore size is what decide what target gas or VOC get adsorbed and what not. However, we can't tell if seller is lying on the gas or liquid phase designation for the AC. Activated Carbon Classification
The snorkel you use is good, it has to be big ID when using a long one, that is correct. Bigger hose ID gets lower resistance and lower resistance is good for your stage one during suction or piston down. Too much resistance, the suction will take more oil mist from the piston rings.
On the CO issue of that lady compressor, I told her to operate it in a 100% open air situation. No one sells a P21 cartridge with Hopcalite locally. The compresor is mobile and not locked down to any one room so she can't do the exhaust pipe extension. The CO test was purely my experiment for the sake of experiment, which benefited her.
I buy mine from the RAE dealer in Singapore, approx US$250 but landed Singapore, so its decent.
Changing sensor for RAE will be approx US$150 in Singapore.
For all intent and purpose, if USD250 is a 3 year use for us non-8 hours a day worker, so be it and we treat it as disposable.
You can buy in-line one from Analox but it cost much more and you cant take it with you on a dive, the portable ones can and we can install the portable ones on a suction side of any compressor snorkle to detect ambient CO sucked in by the compressor. Say if you travel abroad. Carbon Monoxide: Analox - Looking after the air you breathe.
I only use RAE brand because the Singapore support is good and the product proved reliable.
The air fill center in Bali where I play with my expertiment is a Scubapro Center, they are not dive center, only dive gear sales. dive sport
The air fill center is actually at their new location at Sanur and it is not in the website, call them up and ask.
It seems that the more filters you have, the greater release of CO2 there will be from the Molecular Sieve when a compressor is started after a resting period.
How long do you run your compressors with the whip open to allow for this CO2 to escape? The more filtration you have, it seems the longer you may need to run your compressor with the dump or whip open.
Jim, Craig, Pesky, Tobin or others - any thoughts?
From what I've been told by a reliable source, it is true if you don't use a PMV and keep the filtration tower under constant PMV pressure. Most people however do have a PMV and therefore the MC will not allow the release of the CO2.
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Originally Posted by divingtactics
