mk17 IP

[noj3333]

I have a brand new mk17 and while hooking up my spg/ lp hose I thought I'd throw my IP gauge on it. It reads 145psi with the tank at 2000psi (and locks right up, holding steady after each purge of the 1st stage).

Is that in spec? It seemed high to me, but with my VERY limited knowledge I thought it'd be good to check.

 

[lowviz]

It is high, set for "anticipating your next breath".

I dropped mine to midrange. Here is a vid if you are so inclined:

 

[guruboy]

Never worked on a Mk17 but 145 is at the high (but acceptable) end of the mk20/25 IP spec range.

 

[snowdog61]

125-145 is the usual spec range. As long as it locks up solid it is good. If you've got the gauge, you might as well adjust it back to the nominal 135

 

[buddhasummer]

You want to set your Ip at low tank pressure (500psi) due to SP ip "inversion". Ip increases as tank pressure drops. If you set at high end at 3000psi you could be out of spec at low tank pressure. Literature says anything from 5-12psi, evidence of some precision engineering. I have one where ip increase is 5psi and another that is just over 10psi, I guess the latter one was at the end of the machining day. On my ancient conshelf ip increases by a few psi ditto my Apeks, it's negligible. My new found knowledge.

 

[snowdog61]

You want to set your Ip at low tank pressure (500psi) due to SP ip "inversion". Ip increases as tank pressure drops.........

and THIS is why I like coming here.... you never know where you'll find those little golden nuggets.

 

[PfcAJ]

It is high, set for "anticipating your next breath".

I dropped mine to midrange. Here is a vid if you are so inclined:

Good video except for the opv stuff. Completely not needed.

 

[WantSomeScuba?]

You want to set your Ip at low tank pressure (500psi) due to SP ip "inversion". Ip increases as tank pressure drops. If you set at high end at 3000psi you could be out of spec at low tank pressure. Literature says anything from 5-12psi, evidence of some precision engineering. I have one where ip increase is 5psi and another that is just over 10psi, I guess the latter one was at the end of the machining day. On my ancient conshelf ip increases by a few psi ditto my Apeks, it's negligible. My new found knowledge.

This is the right answer with any "over-balanced" reg. Start at 500 PSI and have it lock at 145. Anything from 125-145 is acceptable, but best practice is 145 @500 PSI, and then check it on a tank @3000 PSI and make sure there isn't an unacceptable swing one way or the other.

 

[lowviz]

...//... Start at 500 PSI and have it lock at 145. Anything from 125-145 is acceptable, but best practice is 145 @500 ...//...

Best practice for warm vacation diving or really coldwater diving?

 

[WantSomeScuba?]

Best practice for warm vacation diving or really coldwater diving?

Considering Scubapro taught me one way to tune regs... yes?

I know there's wiggle room, and it doesn't have to be that exact based on specs, but that's what I was told to aim for, regardless of where anyone is diving. So I would imagine warm vs. cold isn't an issue, but I may be wrong.