closed circuit cracking pressure

[kombiguy]

I cannot seem to adjust the cracking pressure of the Se7en mouthpiece. By the time I get the cracking pressure down to 50 cm, it free flows like crazy in OC. the IP is spot on at 123 psi. Any hints or tips on where to look? I'm thinking I have a bad gauge, but it's a poor workman that blames his tools!

 

[tbone1004]

50cm you won't be able to breathe... 50mm maybe?
It is likely a bad gauge. Check it against the "field service" marks *which I can't remember of they're on the BOV or not, mine is at work right now. If it doesn't have them, then look at the manual and figure out where they would be and check it that way

 

[rsingler]

@RainPilot

 

[RainPilot]

Hmmmmm.... I assume you are adjusting only in CC position, should be 30cm in that and then OC will be what it will be. Is it also free flowing in OC if the purge/exhaust diaphragm is removed? If the pilot needle is touching the diaphragm when you rotate to OC then it will free flow, I have seen that happen due to bent pilot or such.

Did you do a service or are you only adjusting the cracking pressure? If you haven't done a full service I would suggest checking for any dirt or encrustation on the pilot as well as the blue membrane inside the "rocket".

Another common issue is if you have misaligned the rocket on replacement. In that case, when the unit is rotated to OC vs CC it pushes the pilot against the exhaust diaphragm. Easy way to check is to remove the purge button and the diaphragm under it and check if it now free flows in OC. If not, it's a pilot pin issue.

 

[RainPilot]

30cm is normal for CC, which then ends up a lot lower for OC.

 

[kombiguy]

Hmmmmm.... I assume you are adjusting only in CC position, should be 30cm in that and then OC will be what it will be. Is it also free flowing in OC if the purge/exhaust diaphragm is removed? If the pilot needle is touching the diaphragm when you rotate to OC then it will free flow, I have seen that happen due to bent pilot or such.

Did you do a service or are you only adjusting the cracking pressure? If you haven't done a full service I would suggest checking for any dirt or encrustation on the pilot as well as the blue membrane inside the "rocket".

Another common issue is if you have misaligned the rocket on replacement. In that case, when the unit is rotated to OC vs CC it pushes the pilot against the exhaust diaphragm. Easy way to check is to remove the purge button and the diaphragm under it and check if it now free flows in OC. If not, it's a pilot pin issue.

Whole 2 year service. I adjust in OC so I have access to the lock screw, then switch to CC to check. I'll check what you suggest, thanks!

 

[RainPilot]

I was taught to ALWAYS adjust in CC, or otherwise “bad things would happen”. I never quite understood why one couldn’t do it the way you did but maybe this is why ?

 

[kombiguy]

I was taught to ALWAYS adjust in CC, or otherwise “bad things would happen”. I never quite understood why one couldn’t do it the way you did but maybe this is why ?

OK, maybe I've been doing it poorly all along. I'll give it a shot!

 

[kombiguy]

Got it done your way, RainPilot. Works fine now. Thanks!