MCH6 Filter lifetime

[h90]

I talked to Lawrence Factor about this some time ago, and was told they rated their MCH6 cartridge for 1800 cf, but that is at the industry standard 80F inlet temp . That would work out to about 28 80s (500 to 3000psi), or 10 hours of operation, half the 20 hours the current manual claims. I asked Coltri about this once and was told to use LFs numbers if using LF cartridges. However, since filter inlet temps tend to be about 20 degrees higher than ambient, on a typical 80F summer day you'd be seeing an inlet temp of 100F, which would reduce filter life at least by half.

My old MCH6 had a sticker on it saying the change the filter every 50 hours! Of course, that was for the old style opaque orange cartidge, which had only carbon in it, so it had little ability to remove water or oil, so it could be counted on the last almost forever.

Europeans have traditionally live dangeously when it comes to filtration, and recommendations from that side of the pond should be regarded with extreme skepticism - last thing I knew, Coltri was still selling the orange cartidge over there.

yes 10 hours sounds reasonable. Thanks!
The guide tells
20 Degree C 68 F: 35 hours
30 C 86 F: 20 hours

And now it get really really weird....
There is a 80 l/min and a 100 l/min version (only the motor is different the filter is the same): With the 80 l/min version it claims you can fill 56!! 15liter tanks from 0-200 bar. With the 100 l/min even 70 tanks. (interesting that the filter can absorb more if the air flow is faster).
(at 30 degree: 32 and 40 tanks).

I have serious doubts on Coltris mathematics....

 

[rcontrera]

I have been selling Coltri stuff for a while now and still haven't figured out a hard and fast "rule" for the filters. I have done several tests for personal amusement/training and, in the NW USA (semi-humid) during the Summer, I have gotten 25-30 fills before the indicator was used up on the LF filter that is made for ColtriAmericas while in the Winter I have gotten up to 40 fills.

If there is any doubt, invest in a moisture eye on the outlet of the filter.

 

[Peter_C]

My Max-air needs the first filter (Inside the compressor) drained fairly often. I have auto drains but for some stupid reason they only put a manual drain on the filter. It catches water very well. If I didn't have a secondary LF filter I would change the first one more often. Whether I should do it more often or not I change the oil every 50 hours and it comes out clean using Nuvair 455. I continuous blend 32% nitrox 100% of the time.

A secondary filter would be a wise investment at some point.

 

[oxyhacker]

Good advice, to which I would add get the lowest % H20 disk available, and don't bother with the combo CO/H20 ones.

When I had my MCH6 I made another, larger, hand packable stack for it out of a $40 surplus hydraulic canister (Sheldon Sporting Goods used the have them, but I think he's out). I cut open an old Coltri cartridge and modified it so it could be repacked, and kept it filled with just 13X. I don't like the idea of trusting a refilled non-refillable cartridge for primary filteration, but as a prefilter it worked great since it was very quick and easy to refill.

The big problem with the MCH6 filter is it is just too damn small - it was designed back when the dangers of inhaling oil, and the value of molecular sieve, were not generally recognized, to hold just a little bit of carbon, and just can't hold enough media to do the job right. I argue this with Coltri every year at DEMA, but they just don't seem to get the point. That's not to say its unusable, just that your safety margin is so small that you really got to keep your eye on it since missing one drain can wipe out the cartridge.

If there is any doubt, invest in a moisture eye on the outlet of the filter.

 

[h90]

Good advice, to which I would add get the lowest % H20 disk available, and don't bother with the combo CO/H20 ones.

When I had my MCH6 I made another, larger, hand packable stack for it out of a $40 surplus hydraulic canister (Sheldon Sporting Goods used the have them, but I think he's out). I cut open an old Coltri cartridge and modified it so it could be repacked, and kept it filled with just 13X. I don't like the idea of trusting a refilled non-refillable cartridge for primary filteration, but as a prefilter it worked great since it was very quick and easy to refill.

The big problem with the MCH6 filter is it is just too damn small - it was designed back when the dangers of inhaling oil, and the value of molecular sieve, were not generally recognized, to hold just a little bit of carbon, and just can't hold enough media to do the job right. I argue this with Coltri every year at DEMA, but they just don't seem to get the point. That's not to say its unusable, just that your safety margin is so small that you really got to keep your eye on it since missing one drain can wipe out the cartridge.

I hope to find somewhere on ebay and old filter which I can add, but that will need a while....
How much is a cheap H2O Disk and is it simple to use? (I use steel cylinder so moisture is more harmful than on the Alu).
here in Thailand it happens often that there is oil in the tank....it is almost normal . Seems some change the filter when too many customer complain

 

[CraigAClark]

Filter towers, being pressure vessels, have a cyclical life. I would never consider buying used towers if the seller can't prove the number of cycles it has been exposed to.

Craig

 

[oxyhacker]

The disks I mentioned are the sensor disks that go inside the eyeball moisture detectors that Ray mentioned. These detectors cost about $70 and monitor filter quality by measuring the amount of moisture in the output from the filter stack. If the air is dry, then you know the filter is working, but when the output moisture level increases then you know the filter cartridge is giving out. The sensor disks come in different ranges, and you really want the lowest % one you can find (usually 20%, I think) so you get a good, early warning. Moisture level is important since the 13X in the filter cartridge absorbs both water and oil, so once the filter stops absorbing water it also can't remove oil anymore.

The problem with the ones that also monitor CO is that they usually have just a single 40% indicator for H20 rather than 20/40/60 or so like the H20-only version, and the CO element has a very short life compared to the H20 elements, so they must be replaced very often, and are so slow acting as to be of limited use.

How much is a cheap H2O Disk and is it simple to use? (I use steel cylinder so moisture is more harmful than on the Alu).

 

[rjack321]

10/20/30 % relative humidity disks are the type you want.
Scuba Compressor

With the tiny filter the whole disk will be "blue" (dry) for up to 9-10hrs in summer here (year-round for you). And then suddenly (<1hr use) go completely pink in all sectors when moisture has completely saturated the cartridge and its not working anymore.

Replace the filter cartridge and use tweezers and a hair drier to rejuvenate the sensor disk. If the disk doesn't get completely soggy wet or oil soaked they are re-usable for years.

 

[rcontrera]

The disks I mentioned are the sensor disks that go inside the eyeball moisture detectors that Ray mentioned. These detectors cost about $70 and monitor filter quality by measuring the amount of moisture in the output from the filter stack.

That $70 moisture eye comes with a 10/20/30% indicator card. It has 1/4 NPTF inlet and outlet so you may need to get the proper adapters to put it in line on your system.

 

[h90]

Filter towers, being pressure vessels, have a cyclical life. I would never consider buying used towers if the seller can't prove the number of cycles it has been exposed to.

Craig

Really? We have a lot customer who use high pressure hydraulic made 50-60 years ago, some worked 24/7 since decades, just grinding the cylinders new and replacing the seals. Is air pressure more problematic or less good built?