I'd like to get some opinions on the probably cause for an issue I have been having with my Nauticam housing for Olympus mirrorless.

As a preface - I generally set up my camera the night before, including pumping the vacuum, so that in case of any slow leak or other issues, there is a full night for said issues to make themselves known.

In Egypt, I was using a new 7" port (one I had picked up from a fellow member here) for the first time and I think I got a drop or two of water into the housing when I opened it, causing the moisture alarm to start flashing blue/red whenever I turned it on. I let it dry out and it seemed to work well enough.

Then in Raja Ampat last October, with the same 7" port, I had the same issue, this time while diving. The light went from green to flashing blue/red on the second dive of the day. There wasn't any visible water in the housing, so I kept diving and did a third dive without any issues. There was still vacuum inside - I had to release it for quite a bit before I could open the case. But there was a drop or two of water inside. After that, the housing was acting up for a while even on land: it would turn green after vacuum sealing for a bit before going back to flashing blue/red (no leaks though). Changing the battery didnt help.

So I sent the housing off to a dealer to check - but he was unable to replicate the problem. The housing was holding a vacuum perfectly for a couple of weeks - all green. When I got it back, I took the housing into a pool and pressed a bunch of buttons - seemed to be working fine and again no issues. I then took the setup to Maldives in Feb, this time with my original 4.33" fisheye port. No issues whatsoever - got 15 dives without any issues. So I attributed this to a glitch/temporary demonic possession and moved on with my life.

Last week, I attached a macro port to the housing and took it in the water in Philippines - after the first dive, we were back to the flashing blue/red light. I dried up the housing thoroughly and opened it - again, a couple of drops of water inside. Came back home and left the case open for a few days, and now it seems to fine.

I have come up with the following possibilities:

1). Faulty moisture sensor: this is ruled out by the fact that I did have a drop or two of water inside.

2). A leak caused by the port: unlikely for 2 different ports to have the same issue

3). A leaking button: possible but what are the odds this button would cause an issue right away on one dive but let me do 15+ dives earlier without any issues?

4). Condensation from humidity forming inside the housing and triggering the alarm: but is there enough humidity in the air inside a housing to do this? I wouldnt think so.

Has anyone encountered something like this?

Edited April 23Apr 23 by vkalia

1 hour ago, vkalia said:

4). Condensation from humidity forming inside the housing and triggering the alarm: but is there enough humidity in the air inside a housing to do this? I wouldnt think so.

I vote for this.

I’ve never used a mirrorless housing in a tropical climate—only small GoPro cases, where I’d place a little moisture-absorbing pad inside. Still, every time I opened the case, the pad was visibly damp. It’s incredible how much humidity can build up in the tiny space left by a GoPro inside its housing.

Secondly, I would check the section of the housing where the port attaches.

P.S.

Do you mind if I slightly edit your title to reflect the actual problem/content?

19 minutes ago, Davide DB said:

I vote for this.

I’ve never used a mirrorless housing in a tropical climate—only small GoPro cases, where I’d place a little moisture-absorbing pad inside. Still, every time I opened the case, the pad was visibly damp. It’s incredible how much humidity can build up in the tiny space left by a GoPro inside its housing.

Secondly, I would check the section of the housing where the port attaches.

P.S.

Do you mind if I slightly edit your title to reflect the actual problem/content?

Hmm, that's a good point. And it is possible that the initial drop of water in the alarm may have made it more sensitive to humidity.

And yes, please, feel free to edit the title. Sorry about that - usually am more descriptive, not sure where my brain was when I wrote this.

1 hour ago, vkalia said:

I'd like to get some opinions on the probably cause for an issue I have been having with my Nauticam housing for Olympus mirrorless.

As a preface - I generally set up my camera the night before, including pumping the vacuum, so that in case of any slow leak or other issues, there is a full night for said issues to make themselves known.

In Egypt, I was using a new 7" port (one I had picked up from a fellow member here) for the first time and I think I got a drop or two of water into the housing when I opened it, causing the moisture alarm to start flashing blue/red whenever I turned it on. I let it dry out and it seemed to work well enough.

Then in Raja Ampat last October, with the same 7" port, I had the same issue, this time while diving. The light went from green to flashing blue/red on the second dive of the day. There wasn't any visible water in the housing, so I kept diving and did a third dive without any issues. There was still vacuum inside - I had to release it for quite a bit before I could open the case. But there was a drop or two of water inside. After that, the housing was acting up for a while even on land: it would turn green after vacuum sealing for a bit before going back to flashing blue/red (no leaks though). Changing the battery didnt help.

So I sent the housing off to a dealer to check - but he was unable to replicate the problem. The housing was holding a vacuum perfectly for a couple of weeks - all green. When I got it back, I took the housing into a pool and pressed a bunch of buttons - seemed to be working fine and again no issues. I then took the setup to Maldives in Feb, this time with my original 4.33" fisheye port. No issues whatsoever - got 15 dives without any issues. So I attributed this to a glitch/temporary demonic possession and moved on with my life.

Last week, I attached a macro port to the housing and took it in the water in Philippines - after the first dive, we were back to the flashing blue/red light. I dried up the housing thoroughly and opened it - again, a couple of drops of water inside. Came back home and left the case open for a few days, and now it seems to fine.

I have come up with the following possibilities:

1). Faulty moisture sensor: this is ruled out by the fact that I did have a drop or two of water inside.

2). A leak caused by the port: unlikely for 2 different ports to have the same issue

3). A leaking button: possible but what are the odds this button would cause an issue right away on one dive but let me do 15+ dives earlier without any issues?

4). Condensation from humidity forming inside the housing and triggering the alarm: but is there enough humidity in the air inside a housing to do this? I wouldnt think so.

Has anyone encountered something like this?

I have encountered similar problems with all my Nauticam housings/moisture-detector over the years (EM5II, EM1II and A7R5):

The housings for EM5II and EM1II were purchased second hand. Very reproducible the moisture alarm went on just after pumping "in" the vacuum 😄, when the housing was assembled in conditions of high humidity (e.g. in a ship's belly or in the tropics at 100% humidity). This was really annoying and I solved this by clipping off one wire that leads to the moisture detector (= two open contacts that are connected upon becoming wet) and making the "detector" thereby less sensitive. There is a tread about this in the old forum, but I just cannot find it right now...

I did not encounter the same problem (= moisture alarm without water drops in the housing, just caused by high humidity) so far with my A7R5 housing, which I bought new. There was a similar problem, when the 140mm domeport became foggy in a cold mountain lake during two dives on the same day, the alarm stood green and did not indicate water or even moiusture. I found about 2 tea spoons of water inside the housing afterwards (the water was inbetween extension and domeport, not directly in the housing). Since the housing was assembled in a heated room and temperatures outside and in the lake were very low, the condensation formed from the water that entered the housing via the leak. The water ingression was probably formed via an old-style N120 extension, were Nauticam had fixed an essential mechanical part with just one screw (instead of four) and this single screw had become loose, but I did not notice (also tread in old forum: https://wetpixel.com/forums/index.php?/topic/71358-dimensions-of-screws-for-nauticam-n120-extensions/&tab=comments#comment-453113)...

=> In principle all of the scenarios you mention are possible. When moisture alarm goes on, just after applying the vacuum and assembly in high humidity, it is likely 4). But then there is probably no water inside detectable, it is just moisture...

When there is a miniscule leak (as was the case with my A7R5), there is little water inside (but the neither moisture alarm nor vacuum alarm reacted in my case, because the water was far away from the detector)...

Wolfgang

Edited April 23Apr 23 by Architeuthis

P.S.: when diving in the ocean, you can easily discriminate between condensation and leak by tasting the few droplets inside the housing...

I do find that my leak sensor, a Vivid Sentinel, can switch from hours of steady green to blinking green/red through, I think, temperature variations - although it’s supposed to compensate for that.

The fact you are getting moisture though is concerning. Good idea from Wolfgang to taste the water. If unsalty then condensation is the likely answer. I did think though that aluminium housings were not especially prone to that. But maybe it’s possible in tropical environments or where there is significant ambient temperature fluctuations, like the mountain lake.

You could try packing the housing with tissue paper and taking it for a dive and seeing where the moisture is developing. This also might help show up the site of a possible small leak as it’s likely to only set the area around the leak whereas moisture would likely be more widespread.

Good luck tracking it down. An annoying and troubling issue for sure.

First I think refer to instructions when diagnosing:

Alternating blue and red is saying the vacuum has gone, but you report the the vacuum still present, indicating perhaps a problem with the pressure sensor.

The moisture alarm is separate to this and is described on the previous page on my manual. It talks about testing the moisture alarm by shorting the two wires of the probe. The response to this is a loud alarm and a flashing red light - not a red/blue light. You're not mentioning hearing the alarm and not reporting the flashing red light so this says that the moisture alarm has not gone off, only the vacuum alarm. You need more than a drop or two to set it off unless it drops directly onto the little sensor. Basically it needs enough of a flood to cover the two wires and complete the circuit, something like 2-3mm in the housing base.

That's not to say the drops of water aren't involved, perhaps the humidity or drops of water have made it onto the pressure sensor somehow? The sensor seems to be within the little black box of the alarm electronics, there is hole on the box which looks to me to be the sensing element. Reading up the sensing element doesn't seem particularly moisture sensitive, but condensation on the electronics may cause issues.

Probably the most likely cause for a drop or two of water inside is water beading on the o-ring and stuck behind it when you open the housing. I always see a drop or three clinging to the o-ring and on the sealing surface when I open up. This is water that has beaded on the o-ring - the o-ring needs to be exposed to water pressure to seal and it will bead up the the o-ring and sealing surfaces. It is held inside the groove/joint by capillary forces. I always remove the o-ring and dry it off to make sure it doesn't get pushed into the housing when closing the clam shell type back,.

Where exactly in the housing do you see the water drops - in the port, inside the housing itself or only along the o-ring sealing surfaces?

So this sordid story of saturated sensors just had another twist: the housing was lying sealed on the dining table for the last couple of days, and the sensor went blue/red again. So I am inclined to think it is an issue with the sensor.

6 hours ago, Architeuthis said:

Very reproducible the moisture alarm went on just after pumping "in" the vacuum 😄, when the housing was assembled in conditions of high humidity (e.g. in a ship's belly or in the tropics at 100% humidity). This was really annoying and I solved this by clipping off one wire that leads to the moisture detector (= two open contacts that are connected upon becoming wet) and making the "detector" thereby less sensitive. There is a tread about this in the old forum, but I just cannot find it right now...

So in my case, until today, the sensor only starts to flash after a while. A few times, once I take it in the water and a couple of times on land. I will try clipping off one of the wires and see if that makes a difference.

6 hours ago, Architeuthis said:

P.S.: when diving in the ocean, you can easily discriminate between condensation and leak by tasting the few droplets inside the housing...

Hmm, good idea. I will try this. I dont know if the drop is going to be large enough to offer a proper taste - each drop is about the size of the condensation droplets that form on bottles, and there are only one or two of them

5 hours ago, TimG said:

You could try packing the housing with tissue paper and taking it for a dive and seeing where the moisture is developing. This also might help show up the site of a possible small leak as it’s likely to only set the area around the leak whereas moisture would likely be more widespread.

This is a great idea!!

2 hours ago, Chris Ross said:

The moisture alarm is separate to this and is described on the previous page on my manual. It talks about testing the moisture alarm by shorting the two wires of the probe. The response to this is a loud alarm and a flashing red light - not a red/blue light. You're not mentioning hearing the alarm and not reporting the flashing red light so this says that the moisture alarm has not gone off, only the vacuum alarm. You need more than a drop or two to set it off unless it drops directly onto the little sensor. Basically it needs enough of a flood to cover the two wires and complete the circuit, something like 2-3mm in the housing base.

<snip>

Where exactly in the housing do you see the water drops - in the port, inside the housing itself or only along the o-ring sealing surfaces?

Oh, that is super helpful. I have always thought that the flashing red light was loss of vacuum (as that's what happens when I release the vacuum at the end of the dive) and red/blue light was moisture. You are correct - the actual leak alarm doesn't go off, only this red/blue light.

As for the water drops - there is usually one drop or so inside the rear cover, in one of bottom metal folds - this could be something that has fallen in when opening the case. But I noticed one drop of water inside the front part of the clamshell, way further inside than one would expect from an O-ring. I also made a big effort to dry the case thoroughly before opening, just to prevent this.

Based on the most recent incident, I can think of 2 possible explanations:

1). A slow leak that is enough to set off the vacuum seal alarm, but not enough to re-pressurize the housing immediately

2). A faulty sensor

The only argument against #1 is the fact that there was a period between the various incidents when the housing worked flawlessly.

I am going to set up the housing again, and leave it for a week or so, to see if this repeats - and then leave it flashing for a few more days, to see if it does lose the vacuum entirely. If there is indeed a loss of vacuum, I will repeat with the 4.33" dome port which was working properly.

On a separate note - are there third party sensors that are worth looking into, which might be more robust?

Ok, I feel like a muppet now.

I checked the Nauticam site after Chris's timely reminder to RTFM, and apparently, with the current set of sensors, flashing red/blue means low battery. I had initially ignored that as an option, b/c I had changed the battery in July 2023 and then again in September 2024, and not dived much with it between those 2 periods or between Sep and now.

The water drops inside also threw me off.

Have swapped batteries and re-vacced the @#$er. Let's see how it holds up.

6 hours ago, vkalia said:

Ok, I feel like a muppet now.

I checked the Nauticam site after Chris's timely reminder to RTFM, and apparently, with the current set of sensors, flashing red/blue means low battery. I had initially ignored that as an option, b/c I had changed the battery in July 2023 and then again in September 2024, and not dived much with it between those 2 periods or between Sep and now.

The water drops inside also threw me off.

Have swapped batteries and re-vacced the @#$er. Let's see how it holds up.

The red/blue flashing is supposed to be when you first turn it on only. My battery recently started flashing red/blue when I turn it on, I didn't replace the battery immediately. Pulled the vacuum, went for a dive, came back and dried housing to release vacuum and it only flashes red. The red/blue only happens when it first powers up, pulling the vacuum it goes yellow then green and when releasing turns yellow the red.

I also note that when vacuum starts to drop when releasing vacuum, the initial response is flashing yellow, then flashing red when the vacuum is nearly gone. SO if you have a slow leak it should start flashing yellow first eventually changing to flashing red. If you are not getting yellow first a slow leak seems unlikely to me.

Your water drops sound very much like water clinging to the o-ring, getting rid of them is near impossible, I run my blower along the seam to blow water out, but there's always some clinging to the o-ring and on the housing. I'm resigned to wiping it off then pulling the o-ring to shake dry and drying the groove every time I open up after a dive.

What I am not clear about is the difference between flashing red and flashing red/blue in the table - the table says both are an issue with vacuum. I don't get red/blue flashing when releasing vacuum.

You could get the red/blue coming on if you momentarily lose power, possibly an issue with the battery holder, the wiring or the switch, that would effectively re-boot the system and it would start red/blue flashing as if it just powered on. That one is a bit hard to test as you would need to be under vacuum and green then play with the wiring. Maybe see if shaking the housing a bit triggers anything??

1 hour ago, Chris Ross said:

The red/blue flashing is supposed to be when you first turn it on only. My battery recently started flashing red/blue when I turn it on, I didn't replace the battery immediately. Pulled the vacuum, went for a dive, came back and dried housing to release vacuum and it only flashes red. The red/blue only happens when it first powers up, pulling the vacuum it goes yellow then green and when releasing turns yellow the red.

I also note that when vacuum starts to drop when releasing vacuum, the initial response is flashing yellow, then flashing red when the vacuum is nearly gone. SO if you have a slow leak it should start flashing yellow first eventually changing to flashing red. If you are not getting yellow first a slow leak seems unlikely to me.

Your water drops sound very much like water clinging to the o-ring, getting rid of them is near impossible, I run my blower along the seam to blow water out, but there's always some clinging to the o-ring and on the housing. I'm resigned to wiping it off then pulling the o-ring to shake dry and drying the groove every time I open up after a dive.

What I am not clear about is the difference between flashing red and flashing red/blue in the table - the table says both are an issue with vacuum. I don't get red/blue flashing when releasing vacuum.

You could get the red/blue coming on if you momentarily lose power, possibly an issue with the battery holder, the wiring or the switch, that would effectively re-boot the system and it would start red/blue flashing as if it just powered on. That one is a bit hard to test as you would need to be under vacuum and green then play with the wiring. Maybe see if shaking the housing a bit triggers anything??

So for me, it never flashes red/blue when I turn it on: only solid blue. Then when I pump it, it slowly turns yellow and then green. At the end of the dive, when I re-pressurize it, it flashes to yellow and then red.

This is the table that Nauticam has and it matches my sensor:

https://www.nauticam.com/blogs/news/learn-vacuum-valves

As for the water drops - initially, that was my assumption too: that some water droplets had fallen in when I had opened the housing, and caused the first problem I had with the sensor (in Egypt). After that, I have taken pains to open the housing in a way that water doesn't go in and the location of the drops (way inside) also feels too far in - but yes, it is possible. I am going to try the napkin trick on the next dive to see if that makes a difference.

Could it be that the water drops in the housing and the vacuum sensor are separate problems? If the housing hasn't been serviced in a while, I wonder about the integrity of the small o-rings that keep water from leaking into the housing. I've removed what seems like a lot of sand from some buttons, especially after being rolled in the sand on shore exits.

Also, I may be swimming against the current, but I often dive my Nauticam housings without engaging a vacuum. Worked fine in years past, and I have yet to flood a Nauticam. Some of my plastic housings have bid adios to the great god Neptune, but never a Nauticam.

I was in the middle of posted a question about the battery when you replied. Red/blue flashing is low battery in my experience on Nauticam.

Drops of water in the housing usually means time to thoroughly clean my O-rings. Take them out, run them through a damp paper towel to clean the sand and grit. Then carefully relube and reinstall.

3 hours ago, humu9679 said:

Could it be that the water drops in the housing and the vacuum sensor are separate problems? If the housing hasn't been serviced in a while, I wonder about the integrity of the small o-rings that keep water from leaking into the housing. I've removed what seems like a lot of sand from some buttons, especially after being rolled in the sand on shore exits.

The housing underwent a full service in 2023, so it shouldn't be general degradation (although that's no guarantee of something going wrong). But yeah, as of now, I am leaning towards the water in the case and the blue/red being separate issues. Gonna take it into a deep pool next week and see how it holds up to all the buttons being mashed there.

As for no vacuum - I flooded my old Aquatica system 3 times in the 12 years I had it. User error each time (and also why I have not gotten a CCR, despite being seriously tempted). Now I just like the peace of mind of the vacuum alarm as a safety need against my own carelessness.

@jlaity yeah, good advice. I admit to get a bit lazy and leaving my O-rings in place. Time to remove it and give it a proper cleaning. Thank you for that timely reminder.

I remove my main housing O-ring with each opening and lube it and clean the sealing surfaces. Early on with my then new Nauticam housing I had the steady red light and got confused thinking it meant water inside. I quickly dumped vacuum and opened the housing. Of course, some drops of water went inside just as you describe. I was near Reef Photo so took it there straight away and they cleaned and checked everything over for free. Then I refreshed my read of the OM ;).

I sometimes get the alternating lights when I turn the system on. Usually after a number of dives in a very humid place. Beats me but once pumped the green light stays steady.

I flooded my FIX/S90 and found a tiny piece of black hair wrapped on the case O-ring. Since my wife has short brown hair and mine is some sort of not black hair it was not mine or hers. Where it came from who knows, perhaps the room service ladies. My fault for changing batteries in a hurry and in a dimly lit area. DAN sponsored insurance covered.

Edited April 24Apr 24 by Nemrod

21 hours ago, jlaity said:

I was in the middle of posted a question about the battery when you replied. Red/blue flashing is low battery in my experience on Nauticam.

Drops of water in the housing usually means time to thoroughly clean my O-rings. Take them out, run them through a damp paper towel to clean the sand and grit. Then carefully relube and reinstall.

Just to be clear red/blue flashing is low battery when the system is first turned on, you can pump it down, it will turn to green and continue to function at least initially -eventually the battery will be too low. When you release the vacuum, it then flashes yellow then red. Not red/blue. I tried this just a day or two ago, my battery was due for replacement and it flashed red/blue when switched on, pumped down to green and when released went flashing yellow then red.

Flashing red/blue anytime other than than this is something else, either a fault or resetting the system due to loss of power if the battery is low at the time. My manual says flashing red and red/blue is loss of vacuum, the guide linked above only mentions flashing red for loss of vacuum. It's clear from the behavior of my system that red/blue only happens when first switched on.

Mine will flash red blue at start up sometimes and then sometimes not, on the same battery or even a new battery. When I sent my housing in for service after five years (more or less) I mentioned this phenomena, and they could not replicate and all checked out normal. So, I go on a dive trip, and guess what ------. I just ignore it now and change my batteries on a regular basis. Thus avoiding the scary steady red!

Edited April 25Apr 25 by Nemrod

On my Nauticam systems, I've only ever seen red/blue when I first turn it on for low battery. Loss of vacuum is flashing yellow and then flashing red, which I see every time I open my camera after a dive. I used to think this was a bad design, but realized it's pretty cool that I test the system every time I finish using it.

I'd still like an alarm reset button near the inside of the port so I don't need to open the back of the housing to reset the warning. Although now that I think about it, I suppose that's another point of failure. If there's a leak near the port, maybe that reset button would short and turn off the alarm.

On 4/25/2025 at 2:30 AM, Chris Ross said:

Flashing red/blue anytime other than than this is something else, either a fault or resetting the system due to loss of power if the battery is low at the time.

I already experienced a Red/Blue flashing vacuum light during a dive.

Started to ascend, the light went back to green, hence continued my dive betting on that it was just a system malfunction (I'm a player), the system alternated red/blue and green during the whole dive.

Once up, I checked on land what was going on inside the housing, apparently nothing wet.

Closed and vacuumed the housing until green.

Continued for the 2nd dive,

Same pattern : green then Red/Blue sometimes back to green.

Back to the hotel room I changed for a new battery and everything went back to normal the day after.

15 hours ago, Luko said:

I already experienced a Red/Blue flashing vacuum light during a dive.

Started to ascend, the light went back to green, hence continued my dive betting on that it was just a system malfunction (I'm a player), the system alternated red/blue and green during the whole dive.

Once up, I checked on land what was going on inside the housing, apparently nothing wet.

Closed and vacuumed the housing until green.

Continued for the 2nd dive,

Same pattern : green then Red/Blue sometimes back to green.

Back to the hotel room I changed for a new battery and everything went back to normal the day after.

It seems that on occasions it will flash red/blue during a dive but the documentation is not complete enough to tell what it is. My manual says it loss of vacuum, but the website doesn't mention that. In this case changing the battery helped, but the OP said they changed the battery out but it didn't help. So it seems to me to be some sort of fault in the system.