Vacuum Pump System tutorial for the Seafrogs Salted Line underwater housings

Underwater photographers and videographers are aware of the features and benefits of Vacuum Pump Systems (VPS) for underwater camera housings. Vacuum Pumps and Vacuum Valves are the best photographers’ friends when it comes to checking your underwater housing water tightness and making sure there are no air leaks in your housing before you submerge. One of the most critical success factors that helps getting that magic shot snapped – the photographers’ peace of mind while concentrating on the work. The VPS helps your stay focused and don’t think about the housing seal.

Here is what you are going to learn from this article:

• Why Vacuum Pump System is what you need?
• What is a Vacuum Pump System?
• How to use the Vacuum Pump System?
• How to remove VPS and open the housing?
• What is in the box of our Seafrogs Salted Line VPS?

Underwater photography is an art, but also a science. There are lots of different parameters you need to learn about and consider while preparing for the UW photo or video shooting. Everything around your gear, literally everything, may influence your UW photography session: timing of housing system setup, ambient temperature, setting up the lights and floating arms, humidity differences inside and outside, presence of an air-conditioner, direct sun light, the micro climate in your car trunk and so on. So the one thing that you may want to clear up in the very beginning – the underwater camera housing needs to be water tight for the required depth and reliable.

There are plenty of tips and tricks on specialized UW photography blogs and YouTube channels to educate yourself if you are just beginning to explore the underwater world with a camera. We are offering the following overview of the vacuum pump system basics with a specific detail on the system main elements and functionality. We will focus the Seafrogs Salted Line VPS in our review, but one should understand that most vacuum valve systems work pretty much on the same principles.

Here it goes.

Why Vacuum Pump System (VPS) is what you need?

How to verify that all your manipulations with the housing during the pre-dive setup did not affect the water tightness and your housing is safe to submerge into water?

All underwater housings do water seal with one or two O-rings on the edges of the housing body and the housing back panel, as well as some more O-rings around the lens port and technological holes. When you insert your camera into a housing and close it with the latch-locks or crews, the O-Rings seal off the water under mechanical pressure and allow you to dive with your housing to the depth indicated in the housing depth rating (usually 20-60 meters deep for the mass market housings, our Seafrogs Salted Line Housings are designed for the 60 meters / 195 ft depth rating when used with the Standard Flat Port).

What happens when you insert your camera into a housing and close the back panel? The ambient air from your room or around your boat goes inside the housing together with your camera. And this air sits there with your camera in a closed and sealed case. Depending on the change of temperature or pressure inside the housing, this air may start mis-behaving and might affect your shooting conditions. Same goes for the smallest particles or dust, sand and hair which may affect the O-ring quality sealing.

So, VPS is a solution.

Any VPS can be used for verifying the water tightness of your underwater housing and confirming there is no air leakage that may trigger the housing leak during the dive. Many VPS give you the green light signal that your housing does not leak, but you can not dive with the VPS installed and need to remove it before going underwater. Some more advanced VPS are built to be switched on during the pre-dive checks and can be used underwater during the dive.

Let’s see how it works.

What is a Vacuum Pump System?

All major Vacuum Pump Systems include the following 3 main elements:

1. a one-way vacuum valve
2. LED green/red light indicators
3. A hand pump

Looking at the Seafrogs Salted Line VPS, the one-way valve (pic. 1) is designed to be conected to the dedicated accessory port in a housing and let the air out of the housing without letting any air in, measure the inside pressure and give light indication with built-in LED indicator to signal when the vacuum is reached and there is no air left inside (*).

There is a variety of accessory ports diameters among underwater housings manufacturers used for the vacuum valves, the most common are the 10 mm (~0.4 inch) used in the Salted Line, and there are also the 14 mm (~0.5 inch) and 16mm (~0.6 inch) ports. As you can see on the Pic. 1 below the thread of the valve and other connections are water sealed with an O-Ring to prevent the damage of internal electronic board (PCB) by the sea water.

   Pic. 1  

 Depending on the VPS design by manufacturer, the vacuum LED light indicators can be positioned either on a housing bottom panel or directly on the vacuum valve, like in the Seafrogs VPS-100 system.

The third element, the hand pump, is usually a quite small but effective tool that connects to the valve port through a soft rubber end-cap and helps to pump the air out of the housing (Pic. 2)

 Pic. 2

How to use the Vacuum Pump System?

Since we are reviewing the Seafrogs Salted Line Vacuum Pump system, we will explain in detail how to install and remove the VPS during the pre-vide housing setup:

1. Before inserting the camera into a housing, we recommend going through the overall housing check to ensure all parts and elements are properly greased and ready for the seal and water tightness:

• Check the Port O-Ring and the tightness of the bayonet connection
• Check the Pistol Grip cover lid and its O-Ring for tightness
• Check the Housing O-Rings and make sure there is no sand, hair or other debris around the O-Ring

2. Insert the camera inside underwater camera housing in a dry and low humidity place.
3. Remove the lid from 10mm accessory port on the top of the back plate, make sure the black color O-ring stays in place to seal the upcoming VPS valve:

4. Check that your valve port mount location is clear and free of debris, attach the electronic valve into accessory port by threading it in clockwise until it sits there properly:

5. Unscrew the electronic valve lid and you will see the metal valve button inside:

 

6. Press the metal button inside the valve to turn the LED indicator ON. LED starts blinking RED:

 

 

7. Attach the soft rubber end of the Pump to the valve, keep the Pump in vertical position and start pumping the air out until the RED color LED changes to GREEN: 

8. LED blinking RED indicates there is still ambient atmospheric pressure inside the housing.

8. On average it may take around 15-30 pumps until the LED changes from RED to GREEN indicating that the vacuum inside the housing has been achieved *. We recommend keep pumping for another 2-3 strokes after the LED turned GREEN to make sure there is sufficient pressure inside the housing for the housing seal test. 

10. Remove the Pump and place the protective lid back to ensure airtightness. 

11. Observe the green LED blinking for 15 minutes to make sure there is no air leakage.

12. If LED stays GREEN after 15 min it confirms that your housing is properly sealed and there is no air leakage. You can remove the VPS (**) and get ready for the dive.

In case the green LED turns RED again within the first 15 min, there might be an air leakage somewhere in the housing and we recommend doing another round of housing check before trying again with the Vacuum Pump System setup steps 1 – 10 described above:

• Check the Port O-Ring and the tightness of the bayonet connection
• Check the Pistol Grip cover lid and its O-Ring for tightness
• Check the Housing O-Rings and make sure there is no sand, hair or other debris around the O-Ring

How to remove VPS and open the Seafrogs Salted Line housing:

1. Remove the protective lid from the electronic valve (see point 5 above)
2. Press the button to release the air pressure from the valve (see point 6 above). LED starts blinking red. Note, it is not possible to open the housing back panel prior to the vacuum release.
3. Remove the electronic valve from the housing back plate and put the cover lid back in place
4. Now you can open the housing and take the camera out. Please note, there might be some left-over pressure and O-ring seal still in the housing that keeps the back plate "glued" to the housing. You may need to apply some gentle force to open the back plate.

What is in the box?

Here is what is included in the box with Seafrogs Vacuum Pump System:

• Electronic valve with build-in LED light indicators
• Hand Pump
• Screwdriver (for battery replacement)
• Spare O-Rings
• * Optional: additional vacuum valve interface to 14mm and 16mm accessories ports (may work with housings from other manufacturers)
• * Where allowed by air transportation regulations, we do include the spare CR2032 battery for the valve, otherwise the spare battery is not supplied, only the battery built-in in the valve is included  

5 levels of Salted Line underwater housing water tightness control: 

Did you know there are 5 levels of water tightness protection in the Seafrogs Salted Line Underwater Housing?
Here are all 5 explained for your consideration: 

1. Housing perimeter sealing by traditional 3mm O-Ring
2. Built-in moisture sensor and alarm system on the bottom of the housing
3. Special metal hinge-lock mechanism on both sides of a Housing
4. 100% pre-sale quality control system exclusively implemented only for the Seafrogs Salted Line housing series (and not available for the other regular Seafrogs housings) - our Quality engineers are placing all Salted Line Housings into a pressure machine for 7 ATM / 30 min pressure test before sending the housings to our warehouse. Check our YouTube channel for the video This is how we perform 7 ATM pressure check for every single Salted Line Underwater Housing.
5. And the final one: we are doing the 10 hours overnight housing seal test with the VPS-100 Vacuum Pump System for all customers in Europe before we ship their orders.

The price for the VPS-100 Vacuum Pump System on the Salted Line Europe website is EUR 119, including free shipping in Europe, but excluding 21% VAT tax which is only applicable for shipping to EU countries. And we sell across the globe.

We have implemented all the possible measures to ensure our housings are properly sealed and safe for the underwater use. All housings are sold with verified water seal. Our customers just need to follow the basic safety precautions to continue enjoying the underwater photography and videography for a long time.

Salted Line Europe team

Follow us on Instagram @saltedlineeurope

YouTube tutorials channel: Salted Line Europe

(*) For the sake of simplicity, let’s agree not to engage in the science of physics around the rarefied air and oxygen particles, we will assume a binary situation in this review: either there is air inside, or there is no air.

(**) Seafrogs manufacturer does not recommend diving with the VPS installed, although our Salted Line team has been diving with the VPS occasionally and there were no issues. One of the major benefits of diving with VPS is absolutely no risk of fogging since there is no air to generate the fog, but such practice remains experimental and performed at our own risk.