Location of Holding Tank Vent on 2019 C28?

[GunkHoling]

I believe my holding tank vent is clogged or has a sag in it, and is the culprit for waste flowing back into the head. I replaced the joker valve earlier this year, and the backflow seems to only happen on a warm day or after being underway. I assume the heat is causing pressure build up with no place to escape.

What's the easiest way to inspect the vent hose for either a clog, sag, or even a vent filter install? My holding tank is accessible under a hatch just inside the cabin door, and the vent is on the port side. It's not clear to me how much I'll have to remove to gain access. I have a northwest edition with propane stove. Does this require a removal of the propane stove to access or is there some other access location I'm missing?

 

[marob]

I have a 2021 Cutwater 28 and we have experienced the same issue since we bought it new. The dealer has said this is a known issue and they may have a solution, just waiting for the parts to be sent. Has something to do with installing an item into the discharge line and it is not a joker valve already have one inline. Can’t remember what the part is but will post the results when I install it.

 

[mferguson]

I've recently started having the same issue on my '18 C28, and I was told by the mechanic that I need a new joker valve. Seems there might be more going on than he realizes, so please advise when you hear about that fix from your CW dealer. My CW dealer in CT isn't a CW dealer anymore. Thanks!

 

[ron ak]

I’m all ears on this one too. ‘19 C28 NW Edition. Replaced my joker valve and gate valve summer ‘23. Back flow didn’t seem as bad last summer, but smell, well wasn’t quite as bad but was adding a lot of treatment to head and tank and trying to keep pumped as much as possible. I think a filter on the vent line would help a bunch. I did install an injection system on the flush raw water line, but it was on the intake side of the check valve and all the juice would go out the intake when running. Another one of this winters projects…. Will move injection point to head side of check valve, somehow, not much line available to access.

 

[William Sanborn]

I’m all ears on this one too. ‘19 C28 NW Edition. Replaced my joker valve and gate valve summer ‘23. Back flow didn’t seem as bad last summer, but smell, well wasn’t quite as bad but was adding a lot of treatment to head and tank and trying to keep pumped as much as possible. I think a filter on the vent line would help a bunch. I did install an injection system on the flush raw water line, but it was on the intake side of the check valve and all the juice would go out the intake when running. Another one of this winters projects…. Will move injection point to head side of check valve, somehow, not much line available to access.

One way to check if Black Water tank is pressurized. Slowly loose the sewage pump out plug and see if it blows out (happens quick), you'll then know if vent is plugged. I would then use water pressure to back flush the vent line into the holding tank. There could be solids blocking the tank end of the vent line.

 

[watson1987]

I use the following method to clean my black water vent

Post in thread 'Waste vent lesson!'

Aug 14, 2024

To clear the vent I use one of the following method with a tiny plunger. I tip it upside down in the water, try to keep it full, and quickly tilt it to seal around the vent and haul. From there I try to pump the water-filled plunger into the vent to push anything stuck back into the tank. Sometimes it takes a few plungers full of water

I keep one on board all the time, I use the same procedure for the kitchen sink, as sometimes the vent/drain gets clogged too, and shifting around the debris lets it flow out...

• watson1987

 

[Headlee]

We have a 2015 C28 and probably need to replace the joker valve. I just make sure I keep the flush going for a few extra seconds to make sure everything in the bowl makes the uphill trip to the holding tank. Anything left in the line will settle back towards the toilet and into the bowl if the valve is not in good shape.

As far as smell - we've been lucky so far. I only flush with fresh water. I haven't yet used an air compressor to clear the vent line, but should probably put that on my list of maintenance items.