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Old 03-01-2021, 06:49 PM   #1
Join Date: Feb 2018
Location: Vail ,az
Posts: 47
black water flush

I have a 2017 forrester 3011 DS and when I tried to flush my black water tank I could not get any water to go thru it . I know there is a check valve but I can not find it . looked by the RR sink and by the kitchen sink and it was not there . Does anyone have a guess or know where to find this valve .
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Old 03-01-2021, 07:06 PM   #2
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Join Date: Oct 2017
Location: Delaware
Posts: 240
I have a TT and my black flush is on the passenger side about five ft high. "MY" check valve is just inside where the hose connects. its behind my kitchen sink. If you care to do it, unscrew the connection point from outside and see if its right there. BUT,, if you cant get your hands on it, that wont matter. I dont trust using it anymore. Not being able to actually see it working, mines not worth using. And a real pain in the butt to be sure its properly winterized. Just my opinion.
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Old 03-02-2021, 04:05 PM   #3
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Join Date: Oct 2019
Location: elkhart
Posts: 198
I would check a couple items.

1. flexible hose from to the tank could have a kink. Best way to check is to take the screws out of the exterior balk tank lush input on the outside of the coach and then pull the Black tank flush input and attached hose out of the wall. If approximately a foot of hose comes out the wall the hose was probably kinked. cut six inches off and reattach the flush to the hose ant screw back into the wall.

2. if that doesn't work, check the check valve which should be under the bath lav sink cabinet back toward the sidewall of the coach.

hopefully this helps
Kary Katzenberger
Product Manager
Forest River Class C Division
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Old 03-03-2021, 03:44 PM   #4
Join Date: Feb 2018
Location: Vail ,az
Posts: 47
black flush check valve

Finally found the black water flush check valve . That did not turn out to be the problem . Thanks to Kary Katz for the lead on this . The hose coming from the exterior connection was kinked and sealed off the water supply. For all you owners of a 2017 Forrester 3011DS the check valve is on the drivers side under the closet and behind the drawers (the same place as the LCI CONTROLS ) See attached pictures . This is a very congested and poor area to get access to .
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Old 03-03-2021, 04:37 PM   #5
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Location: South Western PA
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Glad you found the issue and thanks for coming back and letting us know. Even better with the photos.

Makes you wonder what the person installing that line was thinking. Guess they weren't. I have no clue how anyone with enough mechanical knowledge to install that valve could also not see there was an issue with the hose being kinked.
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