1st Stage/2nd Stage Compatibility

[jerry1818]

Hypothetical question:
I have a regulator set and I want to replace the second stage. Am I limited to the same brand/type as my 1st stage? Is it as simple as setting the correct IP or are there other compatibility issues I need to be aware of when mixing 1st stage/2nd stage and octos?

Thanks,
Jerry

 

[Couv]

Hello Jerry,

Welcome to Scuba Board.

Generally speaking, it is very easy to replace a second stage. Most second stage hoses have a 3/8in male end that screws into the first stage and the other end is a 9/16in female that screws onto the second stage body. Care should be taken with this end as you do not want to damage your regulator. If it is plastic, there should be a place for a second wrench (backup wrench) to hold the tension when you remove or replace the hose.

Now, I started by saying "generally speaking" because some first stages do have a higher intermediate pressure, so this could be an issue. Also, there are some units that do not have the standard hose fittings. To give you a more precise answer, please tell us what first stage you have now and what second stage you intend on attaching.

Finally, if the first stage intermediate pressure is steady and within required psi tolerance, it is the SECOND stage that must (might, actually) be adjusted to this pressure.

Good luck,

Couv