Learn: Vacuum Valves

By: Todd Winner

Most Nauticam housings ship with the electronics for the vacuum check and leak detection system installed. Simply install the battery, turn on the system and you have full functioning leak detection. If any moisture comes into contact with the sensor you will get an audible and visual alarm. That is a great feature but it only alerts you after moisture has entered the housing. To take advantage of the vacuum check feature you need to add an optional vacuum valve to your housing. With the valve installed the system constantly measures the vacuum level and reports its status via a multi-color LED easily visible on the housing.  This allows the underwater photographer to confirm watertight integrity even before entering the water and throughout the entire dive. This sophisticated circuit has an advanced temperature compensation capability, so changes in ambient temperature or changes in internal temperature won’t cause a false positive.

M16 Vacuum Valve with installation tool and hand pump.

M14 - M16

Installing a vacuum valve is simple! The valves even ship with the necessary tool to complete the installation and a hand pump to pull the vacuum. Nauticam vacuum valves come in M14 and M16 thread sizes. Check your housing for the bulkhead opening size, it will be clearly marked. Some housings, like compacts, may only have one bulkhead opening. Most DSLR and mirrorless have two or more. if you have a bulkhead opening on the back half of your housing this is a great place to install a vacuum valve but any of the openings will work. The bulkhead openings on the front half of the housing are better suited for accessories that require a connection inside the housing like an HDMI or electronic strobe bulkhead.

Top view of a NA-A7RIII showing 3 bulkhead openings clearly marked. The M14 opening has a vacuum valve installed.

Offset Vacuum Valves

If you only have one bulkhead opening or are running low on openings you can install an Offset Vacuum Valve. Offset valves allow you to install a vacuum valve while still keeping the opening available for other accessories like an HDMI or electronic strobe bulkhead. They are available in both the M14 and M16 thread size.

M14 Offset Vacuum Valve.

Dual Activation Valves

Larger housings like the Digital Cinema System for ARRI ALEXA MINI require a fair about of hand pumping to pull a vacuum. Dual Activation Valves support creating a vacuum with either the hand pump or via a low pressure inflator. Dual Activation Valves come in the M16 thread size in both standard and offset styles. Dual Activation Valves use the knurled knob on the fitting to open and close the valve.

Dual Activation Vacuum Valve with the cap removed. 

Using the System

Building up vacuum:

• Remove the vacuum valve cap.

• Connect the hand pump (or BCD low pressure Inflator hose for dual activation vacuum valve) to the vacuum valve and pump several times until it reaches the target vacuum level. The LED light will turn flashing yellow while vacuum is building up, then steady green when the target vacuum level is reached.

• After the target vacuum level is reached, i.e. steady green light, attach the cap back to the vacuum valve. It is recommended to leave the housing for at least 20mins to ensure it is sealed. If the LED light changes from steady green light to rapidly flashing yellow light, that means there is a leakage. Please check every o-ring and conduct the vacuum test again.

• Please ensure that the cap is attached back to the vacuum valve before going underwater.

• The vacuum can be released by removing the cap and pushing the vacuum release button.

• Reset the system by pushing the reset button or turning the system off and back on.

After start up:

Nauticam Vacuum Leak Check System Tutorial from Nauticam on Vimeo.