MCH6 Filter lifetime

[h90]

Just got my MCH6 and the guide tells the filter can stay 20 hours at 30 degree celcius
When I calculate with the Compressor Filter Life Costings Calculator V2.1 from scubaengineer.com (Stephen Burton). With back pressure maintaining valve set to 100 bar (I bought extra). It gives me 1.42 hours.
20 hours sound a bit long 1.42 hours sound a bit short.
Someone know?
Thanks
h90

 

[CraigAClark]

Many people are shocked at filter life when they calculate for their conditions. Look at the cartridge. How much media do you think it holds? Owning a compressor, as many have said, is a convenience. You probably will only get Grade "D" air as well. Nature of the beast, in order to be portable.

Craig

 

[h90]

Many people are shocked at filter life when they calculate for their conditions. Look at the cartridge. How much media do you think it holds? Owning a compressor, as many have said, is a convenience. You probably will only get Grade "D" air as well. Nature of the beast, in order to be portable.

Craig

I have an excel sheet that says Molecular sieve: 25g, Activated Carbon 20g.
I don't know if that figures are correct, but it sounds probable as I just checked the total weight of a replacement filter made from Aluminium (including packing) and it has 182 Gramm.
I got told to install a Pressure Maintaining Valve to improve both filter lifetime and air quality. I purchased that already (not yet installed).
I am in tropical climate and I have steel tanks (15l 300 bar) which are hard to get and I want to avoid rust inside...

 

[CraigAClark]

I can't believe that any company in this day and age would not install a PMV as standard equipment. Most specify that the PMV be set at 1800 psi minimum. The molsieve doesn't work well at low pressure, plus you need dwell time. The higher the PMV setting the longer the dwell time. Mako sets the PMV at 2500 on 6000 psi units.

If your unit is driven by a gas engine, your filter is missing hopcalite. You might want to consider adding additional filtration. Do your instructions state that the filter tower is also a final separator?

Craig

 

[h90]

I can't believe that any company in this day and age would not install a PMV as standard equipment. Most specify that the PMV be set at 1800 psi minimum. The molsieve doesn't work well at low pressure, plus you need dwell time. The higher the PMV setting the longer the dwell time. Mako sets the PMV at 2500 on 6000 psi units.

If your unit is driven by a gas engine, your filter is missing hopcalite. You might want to consider adding additional filtration. Do your instructions state that the filter tower is also a final separator?

Craig

Coltri MCH6 sold in Europe (or Asia) is sold without PMV. Someone told me in USA it is (also?) sold with PMV. Thanks to Mr. Burton from scubaengineer.com I bought a PMV. He told that he really recommend one and, did not sell me one but gave me a link to a cheap source instead. Very kind from him!

Also the shop where I bought the unit told me (not knowing that I bought a PMV), if my tank is total empty to keep the tank valve almost closed first to maintain at least 50 bar in the compressor, else the water separation won't work well.

The compressor is electric driven. It has two "cylinders" one is the water separator, which valve I should open every 5-10 min and one with the filter cartridge inside.

Well it is a very small (80 l/min) and cheap unit, you can't expect everything for such a low price.

What disturbed me a a little bit is that the manual told the filter cartridge comes extra, sealed. But in fact it was installed.
I called the shop and they told me it always comes with it installed already. There is a also a manual water drain valve on the filter cylinder and that valve is not installed when the compressor is new. So just a few cm from cartridge is an open hole.

Considering that the compressor was 1 month at the company who forwarded it to me (their stock looks like a wet cave) and than it was 3 weeks on the seafreight I ask myself if the cartridge is already full saturized with water?

What do you think? I considered to use that filter for the run in (5 min without pressure) than adjusting the PMV to 100-125 bar=1500-1800psi and than change it before filling my tanks? Just to be on the safer side?

 

[CraigAClark]

Coltri MCH6 sold in Europe (or Asia) is sold without PMV. Someone told me in USA it is (also?) sold with PMV. Thanks to Mr. Burton from scubaengineer.com I bought a PMV. He told that he really recommend one and, did not sell me one but gave me a link to a cheap source instead. Very kind from him!

Also the shop where I bought the unit told me (not knowing that I bought a PMV), if my tank is total empty to keep the tank valve almost closed first to maintain at least 50 bar in the compressor, else the water separation won't work well.

The compressor is electric driven. It has two "cylinders" one is the water separator, which valve I should open every 5-10 min and one with the filter cartridge inside.

Well it is a very small (80 l/min) and cheap unit, you can't expect everything for such a low price.

What disturbed me a a little bit is that the manual told the filter cartridge comes extra, sealed. But in fact it was installed.
I called the shop and they told me it always comes with it installed already. There is a also a manual water drain valve on the filter cylinder and that valve is not installed when the compressor is new. So just a few cm from cartridge is an open hole.

Considering that the compressor was 1 month at the company who forwarded it to me (their stock looks like a wet cave) and than it was 3 weeks on the seafreight I ask myself if the cartridge is already full saturized with water?

What do you think? I considered to use that filter for the run in (5 min without pressure) than adjusting the PMV to 100-125 bar=1500-1800psi and than change it before filling my tanks? Just to be on the safer side?

Most filter manufacturers, in addition to the processing capacity, set a shelf life and installed life for their filters. I believe most suggest 6 months as an installed life. Did the shop tell you how long they had the unit before selling it to you? I would seriously question them about this and if the unit was a "demo". Every compressor I have ever delivered to a customer came with sealed, packaged filter cartridges and without a cartridge installed. Personally, I wouldn't trust it.

Wow, this isn't the first time I've heard that the applied physics and chemical life of breathing air filtration varies in different parts of the world. A vendor of mine has actually gotten complaints from the Asian market that the replacement filters they offer for the Bauer Triplex don't last the 50 hours that the OEM filters do. It is interesting that the max capacity of the OEM filter will only yield about 14 hours max on a 3.9 cfm machine, based on "standard inlet conditions". I guess the fact that they can actually see the molsieve saturation in my vendors filter as opposed to the Bauer, makes a big difference. What you can't see can't hurt you!

In any case, you are right in using the filter for run up and then changing before doing any filling. I'm assuming you bought spare filters and they are sealed and within the expiration date.

BTW, Ray Contreras, who is a Coltri distributor and scuba board member, recommends that the oil be changed in the MCH6 every 25 hours. Failure to do so could result in mechanical problems.

Craig

 

[h90]

Most filter manufacturers, in addition to the processing capacity, set a shelf life and installed life for their filters. I believe most suggest 6 months as an installed life. Did the shop tell you how long they had the unit before selling it to you? I would seriously question them about this and if the unit was a "demo". Every compressor I have ever delivered to a customer came with sealed, packaged filter cartridges and without a cartridge installed. Personally, I wouldn't trust it.

Wow, this isn't the first time I've heard that the applied physics and chemical life of breathing air filtration varies in different parts of the world. A vendor of mine has actually gotten complaints from the Asian market that the replacement filters they offer for the Bauer Triplex don't last the 50 hours that the OEM filters do. It is interesting that the max capacity of the OEM filter will only yield about 14 hours max on a 3.9 cfm machine, based on "standard inlet conditions". I guess the fact that they can actually see the molsieve saturation in my vendors filter as opposed to the Bauer, makes a big difference. What you can't see can't hurt you!

In any case, you are right in using the filter for run up and then changing before doing any filling. I'm assuming you bought spare filters and they are sealed and within the expiration date.

BTW, Ray Contreras, who is a Coltri distributor and scuba board member, recommends that the oil be changed in the MCH6 every 25 hours. Failure to do so could result in mechanical problems.

Craig

I trust the shop, because it has a good reputation, delayed the shipping because the compressor did not arrive from Italy. The compressor when arrived at my forwarder was coltri packed (some special foam packing). While the two tanks I bought was packed from the shop in a very strange (from someone with 2 left hands) but expensive way. Unit has a 2010 sticker and I ordered Nov. 2010.
I trust that this is true......
The spare filter I bought (somewhere different) is sealed but WITHOUT expiration date.
I think if it is vacuum sealed the expiration date is not that sensitive. I bought the PMV from Ray Contreras. I told him what I bought and he sent it with the right fittings already installed nice service!!!! My shop told me to make the first oil change between 5-10 hours (because of the run in) and than all 25 hours.

Tomorrow I'll start it

Thanks for your help!

 

[CraigAClark]

The fact that it arrive in the Coltri packaging, makes me think the installed cartridge is probably a "testing" cartridge used at the factory. It was probably left in the filter tower by mistake. It happens. I have had machines delivered to me with the test cartridge in place. They generally are not breathing air cartridges, but just drying cartridges. Good luck and I would contact Ray about a filtration up grade. Might save you some money in the long run and give you better quality air. What is the possibility of getting an air quality test in your area? Give you much better peace of mind.

BTW, if the new filter came from Ray, I wouldn't worry about it being expired.

Craig

 

[h90]

The fact that it arrive in the Coltri packaging, makes me think the installed cartridge is probably a "testing" cartridge used at the factory. It was probably left in the filter tower by mistake. It happens. I have had machines delivered to me with the test cartridge in place. They generally are not breathing air cartridges, but just drying cartridges. Good luck and I would contact Ray about a filtration up grade. Might save you some money in the long run and give you better quality air. What is the possibility of getting an air quality test in your area? Give you much better peace of mind.

BTW, if the new filter came from Ray, I wouldn't worry about it being expired.

Craig

I thought of checking around on the internet if I can get filter towers of a larger broken down compressor, but so far no luck. Air quality test should be available here.
(I thought already of using an old fridge as intake air dryer, but that surely not so beautiful construction in the living room would cause my wife switch into Gaddafi mode...)
Today is the day of the first fill.....

 

[oxyhacker]

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.