Shearwater transmitter failure

[runsongas]

that hole usually holds a one way over pressure relief valve. functions like a burst disc on a tank. someone should have noticed it blowing out.

 

[CWK]

Well, at this point, no harm in unscrewing the battery cap. If there's water inside the case, the transmitter is toast. That is a mounting screw hole that shows in your picture. I wasn't aware that that screw hole that is in your picture communicates with the inside of the case, but I haven't taken that type apart.
If there was just water inside your HP hose, you might consider having your first stage looked at as well. But your transmitter may still be toast. Sorry!

OK. Perhaps more info may help.

- My penultimate trip before the failure was to the Banda Sea where the last dive was on 6 Nov 2019. Tx was functioning normally.
- My next trip was to the Solomon Islands. First dive was on 17 Nov 2019.
- No battery replacement made between 6 Nov 2019 and 17 Nov 2019. Tx was not unscrewed between 6 Nov 2019 and 17 Nov 2019.
- Prior to the checkout dive on 17 Nov 2019, I analysed my Nx and checked tank pressure with the transmitter and my Perdix. Transmitter was reading tank pressure normally.
- Shortly after commencement of the dive, I noted coms failure on both my Teric and Perdix. Coms was never re-established for the remainder of the 10 day trip.
- After the check out dive ended, I changed the battery on the Tx. Battery compartment was dry. I checked tank pressure with a tank on the boat using the Tx and my Perdix. Coms could not be established.
- I then detached the transmitter from the hose and saw some brownish liquid fall out (less than a teaspoon).

I suspect that there was some parts failure. There appears to be some rust stains around the round hole shown in the pix above.

 

[CWK]

that hole usually holds a one way over pressure relief valve. functions like a burst disc on a tank. someone should have noticed it blowing out.

It could have been a sudden and catastrophic failure. The thing that puzzles me is the brown stain in that area, which appears to be rust stains.

 

[CWK]

that hole usually holds a one way over pressure relief valve. functions like a burst disc on a tank. someone should have noticed it blowing out.

The tank was pressurised twice before I noted the failure. The first time was when I checked tank pressure after analysing my Nx. The second time was when the system was pressurised immediately prior to the dive. The blowout could have happened on the second pressurisation. I never had coms at any time during the dive.

 

[scubadada]

I had a PPS transmitter that simply quit working after 7 years and more than 1000 dives. The battery compartment was pristine, no obvious defects anywhere. Mine happened to be an Oceanic and they will replace out of warranty electronics for a flat fee Support » Service through the Huish Return Portal http://huish.returnsportal.net/ In this case I received a new PPS transmitter for $120, it's the one I've been using for the last 2 1/2 years. If yours is another brand, you should inquire about their service plan. You didn't say how old your transmitter was or whether it was under warranty.

Best of luck

 

[CWK]

My transmitter was sold under the Shearwater brand.

According to my logs, tank pressure first recorded for a dive on 10 Oct 2018. There were 334 dives before failure on 17 Nov 2019.

 

[CWK]

Apologies. My bad. A number of dives immediately prior to 10 Oct 2018 were Tec dives done without the transmitter. The actual first dive with the transmitter was on 22 July 2018. There would have been some 530 dives with the transmitter prior to failure.

 

[runsongas]

It could have been a sudden and catastrophic failure. The thing that puzzles me is the brown stain in that area, which appears to be rust stains.

the rust is likely from water ingress. do you observe a leak out from the hole when the transmitter is attached to a tank and pressurized?

 

[CWK]

the rust is likely from water ingress. do you observe a leak out from the hole when the transmitter is attached to a tank and pressurized?

Never noticed any leak from the transmitter. No one I was diving with has mentioned a leak or bubbles from my gear.

I do recall dunking my gear (attached to a tank) under water to inspect for bubbles before because I suspected a leak somewhere in the system. On that one occasion, I found a leak where the tank valve meets the tank and the LOB gave me a different tank and sent the faulty tank for service (replacement of O-ring).l

I have wondered about water ingress. The transmitter's connection to the HP hose was solid when I unscrewed it for inspection after it had failed. Water ingress through my first stage then through the 6 inch HP hose does not seem plausible to me because I believe that the HP port on the first stage and the HP hose would have minute pin prick holes and very little water would get through.

 

[runsongas]

it would be in from the uncovered hole in your transmitter if you were detecting a leak there