2006 Carver 42 SS access to holding tank sensor

[markalexander]

Hello Everyone!

We purchased a 2006 Carver 42 Super Sport in September and so far we love the boat!

It appears the holding tank sensor is not working correctly. It always shows 3/4 full even after a pump out. It's the fireboy gauge type system.

I know the tank is empty after a pump out because I can see there is nothing in the tank when I look at it from the stairs area.

I've searched everywhere online and can't find a thread that talks about or shows how to access the holding tank gauge on our new boat.

I've removed the pie shaped step leading into the 2nd guest cabin but that only allows me access to the bow end of the tank. You can't put your head into the area to see the top of the tank, just not enough room in there. I stuck my hand into the area with and with my cell phone I've blindly taken some photos as best as I can and it appears the gauge and wires are at the middle/aft end of the tank. I've attached a couple of photos.

In the lower 'utility room' storage area where the washer and dryer are located, I've opened the small (about 1ft by 1.5ft) panel on the left under the movable stairs that accesses the area under the guest shower area and see hoses running towards the aft end of the holding tank.

Do I have to remove the entire back panel of that storage area to access the gauge on the holding tank including the cubby hole shelf above and slightly left of the central vacuum?

Or is there another easier access panel from above?

Should I remove the carpet up in the salon area just before the stairs and will that reveal an access panel?

Any help from someone who has had to service this holding tank sensor gauge would be appreciated!

I've been a member here for a couple years (when we owned our Carver 350 Mariner) and have found this forum is so excellent for information, thanks to everyone for all their help and support for us novice owners!

Thank you
Mark

holding tank gauge.jpg

20231010_123759.jpg

[km1125]

The thing you have labelled in the pic as "holding tank gauge" is (I believe) a "Tank Saver" to relieve vacuum in the tank and prevent an implosion (ok, maybe that's being too dramatic... just a tank collapse from too much vacuum when it's being pumped out).

I suspect the tank sensors are in the left edge of the pic (under the 'brown wooden box' and black hose) where there are multiple conductors going into something. There might also be something towards the middle but it's obscured by that black hose.

Looks like you need to explore how to get that "brown wooden box" out of there, or at least the bottom of it, to get better access to that area.

[Midnightsun]

Yep, km1125 nailed that one.

[Viper]

Ya I agree. The item you are pointing to with a sponge in it is a Tank Saver. The black puck with wires going to it on the left corner is most likely the level sensor. How many wires are going to it/hooked up? Hard to tell in the pic.

[markalexander]

Hi,

Yes, I think that km1125 is correct! Those wires are just running over that padded device.

That "box" is in the utility room and I think maybe the floor of that box may be able to be removed. Now that you mention it in your post, it would make sense that the sensor is over by where all the hoses enter the holding tank.

Viper asked how many wires are leading to it and I agree, hard to tell from photos.

I will go through all my photos again but I think this is the best photo of that area of the tank.

I won't be back to the boat until December, but I'll check if that box has a bottom panel that's removable.

Thanks everyone for your comments and help!
Mark

[Viper]

Here is some literature...
https://pdf.nauticexpo.com/pdf/fireboy-xintex/liquid-level-monitoring-system/21916-13512.html

[Viper]

Just throwing this out there; you're talking about the holding tank level showing 3/4 full but the button that you're pushing is typically for the fresh water level, or are both buttons for holding tanks re a 2 holding tank application? If so, is the gauge on the left for fresh water?

[markalexander]

Hi Viper,

Thanks for sending the link. I've read that and used it for my troubleshooting, but didn't help too much

Thank you!
Mark

[bud37]

Have you tried any of the holding tank cleaners, there are many on the market that may clean the sensors if they are the issue here.

[markalexander]

Source of the post Just throwing this out there; you're talking about the holding tank level showing 3/4 full but the button that you're pushing is typically for the fresh water level, or are both buttons for holding tanks re a 2 holding tank application? If so, is the gauge on the left for fresh water?

Hi Viper,

I think you may be on to something here! When I purchased the boat the broker (not the owner) showed me how the tank gauges work (I've not seen these XINTEX gauges before for tank levels) and the broker said the right HOLDING TANK button on the right gauge is for the holding tank, but as you say, there are two buttons labelled HOLDING TANK on that gauge. Also, the gauge on the left only has 1 button to press and the gauge on the right has 2 buttons. The gauge on the left is clearly marked WATER TANK and the gauge on the right is marked HOLDING TANK but shows 2 buttons. I only have 1 holding tank, now I'm confused and don't recall what happens when I press the left HOLDING TANK button on the gauge on the right.

I have 1 holding tank and 2 water tanks. The Port water tank is the inlet from the deck fill at the dock and does NOT have a gauge in the tank. The Port water tank is connected to the Starboard water tank via a large hose that comes off the bottom of each tank. Thus, both tank fill equally as I fill the water system. The Starboard water tank has a level sensor in it. I have photos of both tanks and can confirm this fact. The image I've attached seems to indicate this as the water tanks were empty at the time I took the photo.

When I went on the sea trial in mid September the boat broker told me that he took the boat over and they did a pump-out just before the sea trial and I recall him showing me the gauge and that it still showed 3/4 full even though they just did a pump-out. He said they pumped the boat out numerous times and flushed it because he noticed the HOLDING TANK gauge still showed 3/4 full. The boat broker surmised that there was some toilet paper or something caught in the sensor and that it wasn't working correctly. We left it at that. (In hindsight I probably should have got this fixed as part of the work necessary before I firmed up our purchase)

When I did my pump-out just before haul-out the holding tank still showed 3/4 full. I verified the tank was empty by shining my flashlight through the tank and it sure looked empty. I don't want that tank freezing over the winter....!

I'll need to figure out what the HOLDING TANK button on the left does (if anything) on the gauge on the right, I'll have to wait until late April or early May to troubleshoot this again.

I will post an update once we get the boat back in the water in the spring.

Thanks again for all your help
Mark