Dive Hookah Regulator Question

[resilientg]

Hi There Everyone,

Simple question.

I want to have access underwater to my boat, i only really need to go down a few meters and for no more than an hour.

I'm about to start building a dive hookah to play with, i have a 12 volt 2 cylinder ceramic piston oil free pump that puts out 85 liters a minute and works up to 150 psi.

I have also found a good deal on the regulator, hose, belts etc.

I can buy a nice 40 micron air filter / water trap and make a good stainless charcol filter and air reserve tank, that's all easy, but!

As the pump works at up to 150 psi and the regulator is around 60 psi, what happens with the extra pressure?

i was thinking of installing a compressor pressure switch if needed but i'm not sure if the regulator would just free flow the extra pressure or just die in the attempt?

Ideally it would be nice to have the system reach the required pressure then turn off the pump until the pressure drops enough then restart the pump as then the pumps get some down time to cool off and i save on wasting power.

Any help would be greatly appreciated.

Thanks in advance,

Matthew
SV Defiant

[daddle]

When I bought my hookah rig they used a higher pressure regulator. The higher pressure compensates for dragging the air thru the long hose. The regulator looks the same as any other but must have a tougher diaphram or something.

[Albro359]

I'm looking for a hookah regulator...where do you get them ??

[Albro359]

This is VERY good information...

Intro to Hooka!

[Bricky]

I recently built a hookah for the same reason as yourself. Already had compressor and 15 litre air tank with a 150 psi pressure switch hooked up to it. This should give me a few minutes of air should something go wrong with compressor. I did not bother with a filter as I will not be using for very long. One thing I did was to put an extra tap in the bottom of the tank so when I am finished with it I can drain air and any water that may be in the tank. As far as I know and according to the local dive shop that sold me the reg and hose there is no difference between a normal reg and one used on a hookah.
I have never dived other than with a snorkel but find it great, staying under for half to an hour.
Cheers

[resilientg]

thanks for the posts so far, but no one seems to have touched on the question that was actually asked.

Matthew

[daddle]

Originally Posted by resilientg

thanks for the posts so far, but no one seems to have touched on the question that was actually asked.

Matthew

Compressor controls like you seek are common. Graingers Catalog?

[daddle]

What I was hinting at before was that secondary dive regulators can accept much more pressure as that is what my hookah is set up for. I don't recall what the hose pressure is. Also with a hookah the primary regulators reference is the atmospheric pressure not the dive depth pressure. So for a given depth it will deliver less absolute pressure.

Confused? Ask a pro dive supplier. That's what I did.

[chrisjs]

I have a "hookah" put together as recommended by a dive professional. The system uses a small 120v 2-gallon oil-free compressor. There is no filter. The regulator is a regular diving regulator. The compressor can barely maintain 100psi when I am diving, so "overpressure" is not an issue. But, regardless, the compressor has a simple adjustment to reduce the maximum pressure to the desired level (usually just set to 125psi). I would be very surprised if a 12V compressor will even get to 150psi while you are using the system, and recommend you look for the pressure adjustment valve. On my system the compressor simply shuts off automatically when the set pressure is achieved. I have a 12V / 150psi compressor on my Buell air horn that can barely keep up with maximum air flow!!

[Dulcesuenos]

Not sure if it was said but you should regulate the pressure down to what the reg requires. Otherwise you can damage it, and also put more strain on the hose. Your compressor should have a regulator built in if not you can get one from napa or any parts store.

[tamicatana]

The simplest thing to do...

Use a very long hose between your first and second stages. That's it. Clip the hose to your BC in some way to keep it tidy. **credit FstBottoms

No new compressor, fancy rigging, etc. Tank you prolly already have, first and second stages you already have. Just a long hose.

[fstbttms]

Originally Posted by resilientg

i have a 12 volt 2 cylinder ceramic piston oil free pump that puts out 85 liters a minute and works up to 150 psi.

As the pump works at up to 150 psi and the regulator is around 60 psi, what happens with the extra pressure?

As indicated previously, you do not need to (and indeed, probably cannot) find a 2nd stage scuba regulator to deal with 150 psi. You need to reduce the pressure coming out of the compressor to something the regulator you currently have can play nicely with.

The compressor I use is rated to put out 125 psi. But I find it works fine when I dial back the pressure to about 70 psi. The way to do this is to install a variable pressure relief valve on your compressor. Available from Grainger:



CDI CONTROL DEVICES Valve, Pressure Relief - Compressor Valves - 4TK26|CR25-100 - Grainger Industrial Supply

[fstbttms]

BTW- for working under the boat, a reserve tank and the associated plumbing are completely uneccessary. Should the compressor ever shut down for whatever reason, 50' of air hose will give you enough to get back to the surface easily.

[fstbttms]

Originally Posted by Albro359

I'm looking for a hookah regulator...where do you get them ??

Zeagle makes a good hookah regulator. Try Airline by J Sink:

Air Line Diving System | The Air Line by J. Sink

[Matt sachs]

Maybe I'm confused about hooka, but the typical open circuit first stage reg its set to reduce tank pressure to 140 - 145 psi. The second stage reduces pressure to slightly over abient pressure. Why do you need a special hooka reg if you have 150 at the compressor?