Using Nauticam's Vacuum Leak Detection System

Nauticam now supplies vacuum leak check electronics with all new models of housings for DSLR, Mirrorless, and Compacts.

Why Vacuum Leak Check?

For decades a quick dunk test in the hotel pool has been the recommended procedure to test your housing before every dive.  The Nauticam Vacuum Leak Check can be performed just about anywhere; no need to find a pool or fill the bathtub.  Assemble your system the night before your dive, and if the green light is still on by morning you'll feel confident about your dive from the minute you step onto the boat to the minute you step off. 

The vacuum check uses air, not water, making it easy, fast, and convenient. Simply put, if your housing does not have a leak, your camera will not get wet.

Is a vacuum test reliable?  For any given pressure differential, air will leak much faster than water.  Think about it; a balloon filled with air for your child's birthday will obviously have lost quite a bit of gas by the next morning.  But a water-balloon will likely not leak a drop (until it gets thrown at you.)

How Difficult is it to Use the Vacuum Leak Check System?

If we told you how easy it is, you might not believe us.  So, we have decided to show you how simple it is instead. 

How Does the Vacuum Leak Check Work? 

If you have a leak in your housing while diving, the water pressure will cause water to run past the o-ring, or dirt, or whatever, and into the housing and ruin your camera.  Because we would like to test the housing before we go diving, we can try to create a leak by lowering the pressure in the housing; then air at atmospheric pressure will go through any leak point and into the housing.  If air does leak into the housing, then the pressure inside the housing will begin to rise (just as it would when you were submerged in water.)

The Nauticam Vacuum Leak Check electronics monitor for this change in air pressure, and it is very sensitive.

As you saw in the video above (you did watch it, didn't you?) we use the hand pump to create a mild vacuum.  Vacuum is a relative term; when the pressure in the housing is lower than atmospheric pressure, we call that a vacuum. 

When the Vacuum Leak Check system is first powered on, before you close the housing, the electronics measure ambient pressure and temperature.  When it is ready, the light changes from steady blue to a flashing blue.  Why measure temperature?  You may remember from your scuba diving course that pressure change occurs with temperature change, so to make the leack check system as sensitive as possible, without being susceptible to false alarms, it measures temperature along with pressure.

So turn it on, wait for the electronics to calibrate to ambient pressure and temperature, close the housing, then pump a small vacuum in the housing until the light turns green.  The electronics constantly monitor pressure and temperature, and if it determines that the pressure in the housing changed, and not due to a temperature change, it will change the light from green to yellow or red to alert you.

How Do I Draw a Vacuum for the Test?

There are two easy methods to lower the pressure in your underwater housing.  The method which is best for you is usually dependent on the size of the housing.

Large housings, such as those used for broadcast quality video systems, need to have a significant amount of air removed.  These systems can be hand-pumped or pumped by a special valve powered by your BCD inflator hose.  For DSLR and mirrorless housings and smaller, this method is unecessary and usually no faster than the hand-pump method.

To draw a vacuum with the dual activation valve you may either use the hand-pump or the BCD inflator hose.  To use the BCD inflator hose, remove the protective valve cap, close the vacuum valve, and attach the BCD low pressure inflator hose.  Remove the hose immediately after removing enough air to change the indicator from blue-to-yellow-to-green.

A hand pump and a wrench is included with every vacuum valve.

Which Valve do I Need?

The most important factor in choosing the correct vacuum valve is whether you need a 14mm or 16mm thread for your bulkhead.  Some underwater housing manufacturers, like Nauticam, clearly mark the bulkhead on the outside of the housing.  If the housing is not marked, you will need to either consult your owner manual or measure the thread opening in your bulkhead.

The second factor to consider when choosing your vacuum valve is whether you really need the speed and volume possible with the Dual Activation Valve.  Most divers will prefer the regular vacuum valve and hand pump to draw the vacuum.

In addition to choosing whether you will ever need to use the BCD inflator hose, you will consider if you are using an external HDMI monitor or high definition video recorder, and the number of available bulkhead connections on your housing.  After installing an offset extension with vacuum valve, the bulkhead remains available for use with an HDMI, SDI, or strobe bulkhead.

Please call or email us so we can help you determine which vacuum valve is best for you and your UW housing.