Dive Computer Failure- What Happened?

[KeithG]

100 feet is also nonsense. I take mine down to around 150 feet after each battery change. This is deeper than it will go in real life.

 

[DIVEWATCHDOCTOR]

Giffenk: Concur with the depth you use for pressure testing your dive computer. Unless the client has a special requirement we waterproof every dive computer, transmitter and dive watch we service to 165 feet (50 meters). For that, we use Bergeon 5555/10 pressure tester designed to prevent flooding, even if the computer has a leak. Simple pressure pots used in many dive shops can only perform "destructive tests". That is if there is a leak the computer gets flooded during the test. Contrary to your opinion, we follow manufacturers recommendations and install a new Oring in every computer we service. More at: www.divewatchdoctor.com

 

[DIVEWATCHDOCTOR]

JamesBon92007: Unfortunately sometimes the depth sensor fails to render the dive computer useless. True, this happens across the whole spectrum of brands and models but there is a particular brand in which this is reported more frequently than in the others. To your point, there is nothing you can do to prevent this failure other than continue with the good practice of doing what you do: dunk your computer for 10 to 15 minutes in fresh water after each dive, repeat and rinse the pressure sensor, gently but thoroughly, at the end of every diving day. You certainly will prevent the buildup of salt crystals but pressure sensors are piezoresistive units that can also die of other causes, like any other electronic device.

 

[BillP]

Hi there All. since you are talking about dice computer o-rings just informing you that at scubagaskets we run a 25% discount on all of our dive computer o-rings

Diving Computers O-rings -Scubagaskets scuba o-ring provider

Thanks Scubagaskets. I used your site as a resource to try to find o-rings for my computers. I didn't find my computers listed, which isn't surprising considering their age, but I did find the right size.

Today those o-rings list for 11.50€ for 50 o-rings plus 8.00€ shipping or 19.50€. I didn't see where they were 25% off of that price so I assume that is the discounted price?

That's $22.53USD at today's exchange rate plus a 3% foreign exchange fee from my credit card or ~$23.21 for 50 o-rings or 46¢ per o-ring, I assume shipped from Europe.

So that you know what you're up against, today I also found the o-rings from Scuba Choice via Amazon for $6.48 for 50 o-rings including shipping and tax or 13¢ per o-ring. (They were $6.01 when I ordered them.) They weren't on Amazon Prime, but they arrived 4 days after I ordered them.

Also, on the Amazon website did NOT have a popup for online chat come up on every single page blocking my view of the page. I couldn't use your chat feature because I couldn't find a way to use it without signing up for Facebook, which I don't use. Have you considered a "No Thanks" button on the popup?

Appreciate your input, though.

 

[BillP]

100 feet is also nonsense. I take mine down to around 150 feet after each battery change. This is deeper than it will go in real life.

Unless the client has a special requirement we waterproof every dive computer, transmitter and dive watch we service to 165 feet (50 meters).

It makes sense that you pressure test a computer to deeper than you plan to dive, just as you would buy a dive watch rated to deeper than your deepest dive. My deepest dive was a little over 100' on this trip. My computers claim they are engineered to dive to 325'. I wonder how many computers would survive a test dive to 60' and then fail at 100'. My experience was 1 out of 3, unfortunately.

 

[BillP]

(W)e use Bergeon 5555/10 pressure tester designed to prevent flooding, even if the computer has a leak. Simple pressure pots used in many dive shops can only perform "destructive tests". That is if there is a leak the computer gets flooded during the test.

I seem remember reading in the past that at least some computers need to be immersed in water when under pressure. True?

Addendum: A search of my computers' manual says:

Do not test or use the [dive computer] in pressurized air

And a quick Google search found this warning in the Oceanic Datamax Pro manual:

Warning: Never pressure test the Datamax Pro in an air environment. Doing so may damage the depth sensor; possibly resulting in erroneous depth or time readings.

 

[dmaziuk]

This may be a little to the side of the topic, but I've also been reading about depth sensor failures. I'm wondering if anyone has a solution to help prevent this failure. I intend to thoroughly rinse my depth sensors after each dive with the idea that it might be salt crystals that are the culprit.

Aside from salt, these things do have limited lifespans but there's very little "wear and tear" there. So those lifespans should be pretty long and you would typically be looking at manufacturing defects for cause of failures.

Simple pressure pots used in many dive shops can only perform "destructive tests". That is if there is a leak the computer gets flooded during the test.

Yeah. Dielectric fluids aside and sealed battery compartments notwithstanding.

 

[KeithG]

I seem remember reading in the past that at least some computers need to be immersed in water when under pressure. True?

Addendum: A search of my computers' manual says:

Do not test or use the [dive computer] in pressurized air

And a quick Google search found this line from the manual in the Oceanic Datamax Pro manual:

Warning: Never pressure test the Datamax Pro in an air environment. Doing so may damage the depth sensor; possibly resulting in erroneous depth or time readings.

Depends on the design of the computer. In some (many, most, but not all) the pressure sensor is directly exposed to the ambient environment. Fresh or salt water or air. I believe this style of computer has warnings about exposure to air pressure and likely has a higher failure rate due to salt crystals formation (my opinion, I have no facts to back this up).

We use ancient Uwatec computers that do not suffer any of these issues since the pressure sensor is not directly exposed to the ambient environment.

Simplest description is "dive computer in a bag". The complete computer is sealed inside an oil filled compartment with a large flexible membrane, all placed inside a flimsy plastic shell.

 

[KeithG]

Aside from salt, these things do have limited lifespans but there's very little "wear and tear" there. So those lifespans should be pretty long and you would typically be looking at manufacturing defects for cause of failures.

Manufacturing defects are most likely associated with infant mortality type issues (first couple of years?). My 23 year old computer that went ERR mode last year is not likely a manufacturing defect.

 

[JamesBon92007]

Depends on the design of the computer. In some (many, most, but not all) the pressure sensor is directly exposed to the ambient environment. Fresh or salt water or air. I believe this style of computer has warnings about exposure to air pressure and likely has a higher failure rate due to salt crystals formation (my opinion, I have no facts to back this up).

We use ancient Uwatec computers that do not suffer any of these issues since the pressure sensor is not directly exposed to the ambient environment.

Simplest description is "dive computer in a bag". The complete computer is sealed inside an oil filled compartment with a large flexible membrane, all placed inside a flimsy plastic shell.

When I first decided that I should probably get a computer and was willing to spend up to $20 for one I was looking at some Uwatecs on eBay. Most had dead batteries, so I went on YouTube and learned how to change the battery. I was impressed with the way they were oil-filled and it seemed like, unless it was sloppily re-assembled, it would be very unlikely to ever flood. Some computers I looked at seemed to be using salt water (the ocean) for connections so it was pretty obvious that those contacts would need to be kept clean and a pencil eraser (a standard scuba equipment tool) was suggested. Naturally I thought that most modern computers were equally as resistant to flooding but apparently that is not the case. I recently did a swap for an AquaLung i300 that was nine months old. It failed somewhere between here and Hawai'i. I sent it back to my friend and he got it replaced under warranty. They said it was the pressure sensor. From what I've read on SB about all I can do is rinse thoroughly and hope. Meanwhile, I have a list of recalled Uwatecs (so I know which ones not to get) and I'm keeping an eye open for a good deal on an old Uwatec. They seem to have a faithful following.