K14 Elevated CO2

[CG43]

Plus you're pumping more gas into that filter than required. On tiny (Coltri) filters you simply don't have much filter time to waste.

A small filter needs less air to bring it to PMV pressure. It is the ratio of filter volume to MS quantity that plays a role here.

If you look at videos of the Coltri MCH 6 there are filling hoses without shut-off and ventilation valve.
Here the filter must be completely vented after each tank.
For 95 euro you can buy the shut-off/venting valve.
Whether a PMV is present cannot be said with certainty in every video, but a PMV can be retrofitted for 310 euros.
If you only use the MCH 6 occasionally and operate it with PMV and shut-off/vent valve, so that the filter does not have to be vented after every single tank, the filter will also be able to achieve the specified service life. If I estimate the filter size according to the videos, it certainly looks that way to me and Coltri is a large compressor manufacturer who can calculate and test this .
If in doubt, read the link from happy diver # 20 Scuba Engineer to a larger Coltri with PMV.

 

[Agro]

Coltri is a large compressor manufacturer who can calculate and test this .

Coltri produces loasy compressors, especially MCH6.
Cotri produces loasy compressor parts, for ex. filter including PMV.
Perhaps they can calculate anything but they don't care about it. They sell the cheapest product even if they know it's rubbish.

 

[Simpel]

I found the following in the Bauer Junior 2 manual:
===
CO2 is present in the atmosphere at a natural level of
approx. 350 ppmv, but this value can also vary greatly
. The molecular sieve used for drying is
also capable of adsorbing CO2, among other things. This
accumulates in the cartridge. After the compressor system is switched off, adsorbed CO2 can be desorbed again as a result of the partial pressure reduction. This CO2, which is no longer
bound, is then flushed out of the cartridge when the system is restarted. To avoid increased
CO2 values in the compressed breathing air, we recommend flushing the compressor system for approx. 1 - 2 minutes before
connecting and filling the compressed air cylinders, i.e. releasing the compressed air
into the atmosphere by briefly opening the filling tap
===
Could this explain the excessively high CO2 value?

 

[happy-diver]

Ha ha ha aha mate you're far from Simpel

 

[CG43]

The molecular sieve used for drying is
also capable of adsorbing CO2, among other things. This
accumulates in the cartridge. After the compressor system is switched off, adsorbed CO2 can be desorbed again as a result of the partial pressure reduction. This CO2, which is no longer
bound, is then flushed out of the cartridge when the system is restarted.

That is very interesting!
The best partial pressure reduction is achieved by releasing the pressure from the filter. This way the MS can release the most CO2 .
In order not to have the disadvantage of filling the filter with air that is not optimally dry when restarting, pre-pressurization must be carried out with dry tank air.
The air containing CO2 can also be flushed out in the process.

 

[Agro]

I found the following in the Bauer Junior 2 manual:
===
CO2 is present in the atmosphere at a natural level of
approx. 350 ppmv, but this value can also vary greatly
. The molecular sieve used for drying is
also capable of adsorbing CO2, among other things. This
accumulates in the cartridge. After the compressor system is switched off, adsorbed CO2 can be desorbed again as a result of the partial pressure reduction. This CO2, which is no longer
bound, is then flushed out of the cartridge when the system is restarted. To avoid increased
CO2 values in the compressed breathing air, we recommend flushing the compressor system for approx. 1 - 2 minutes before
connecting and filling the compressed air cylinders, i.e. releasing the compressed air
into the atmosphere by briefly opening the filling tap
===
Could this explain the excessively high CO2 value?

Great! I never ever had a closer look to my Bauer Oceanus (not Junior) manual, I guess there I would find the same information.

From now on I will do as Bauer describes, first flush the system.

 

[grantmac]

Flush, but not depressurize the filter. Which is only possible with a PMV.

 

[Mudbags]

I found the following in the Bauer Junior 2 manual:
===
CO2 is present in the atmosphere at a natural level of
approx. 350 ppmv, but this value can also vary greatly
. The molecular sieve used for drying is
also capable of adsorbing CO2, among other things. This
accumulates in the cartridge. After the compressor system is switched off, adsorbed CO2 can be desorbed again as a result of the partial pressure reduction. This CO2, which is no longer
bound, is then flushed out of the cartridge when the system is restarted. To avoid increased
CO2 values in the compressed breathing air, we recommend flushing the compressor system for approx. 1 - 2 minutes before
connecting and filling the compressed air cylinders, i.e. releasing the compressed air
into the atmosphere by briefly opening the filling tap
===
Could this explain the excessively high CO2 value?

This is the answer right here.

CO2 also has a tendency to build up in filling hoses.

 

[Agro]

This is the answer right here.

CO2 also has a tendency to build up in filling hoses.

In filling hoses?????????? For real? Who sais so? Never ever heard.

 

[Wallowa]

Coltri produces loasy compressors, especially MCH6.
Cotri produces loasy compressor parts, for ex. filter including PMV.
Perhaps they can calculate anything but they don't care about it. They sell the cheapest product even if they know it's rubbish.

Good grief....will you stop with the bashing of Coltri.....I get it you don't like the Italian compressors....not German or Swiss....get off your high horse and present something positive.....you are a broken record.