Community Forums

bneumann · 03-15-2022, 06:08 AM

On 2019 Tiffin Allegro RED 33AA the grey tank sensor all of a sudden is always reading 2/3 full & when drained & then when adding waste water starts reading Full & blinking. The black tank is behaving normally.
RV has been sitting in campground since early January.

Kind of lazy to take a 30 minute drive around to maybe loosen any sludge around sensors, have tried some cleaners, also let it fill up several times & then drained completely. When first noticed something was up it always stayed around 1/3 full.

1. know about see level system of better level control
2. wondering where the sensors are in tank or outside tank wall ?
3. tanks are hard to get to, believe may need to remove an exterior panel passenger side; want to wait until more info is obtained
4. Anyone know of location of any accessible exterior sensor wiring?
5. Spyder panel reporting seems to be OK
6. Wondering why 2/3 & full sensor notification only reporting ... maybe empty or 1/3 full disconnected or not reading due to disconnect, sludge on tank or bad sensor.

Anyone have any thoughts ??

May wait until we leave campground, add some Happy Camper, etc. & let it swirl around.

Also have a flush hose insert at drain pipe .... maybe will try to close the black blade guillotine valve open the grey side & shoot water into grey tank system to stir water in there maybe clean walls etc. The grey tank does not have a flush tank connection like the black tank does.

Otherwise will grin & bear it until it becomes a nuisance. Usually keep the grey tank open at campground, black tank closed until 1/2 full then flush & drain.

Hopefully someone has some ideas ?

**Lt Dan** · 03-15-2022, 07:08 AM

The sensors are on the outside wall of the tank and should be located behind the passenger side panel with the gravity fill. Even on the gray tank, a coating of crud can build up on the inside walls of the tank causing false readings. This is especially true after it's sat for a while and the tanks dry out. Next time you are out in the coach, fill the tank about 1/2 full and put a cup of Dawn detergent and about a quart of Calgon water softener in the tank. Let it slosh around in the tank while driving to your next destination and see if that clears it up. I added a flush sprayer like the black tank to ours to help keep the walls washed off. Just like the black tank, if you'll keep the gray closed until a drain is needed it helps to flush out the grease abd soap scum out of the tank.

RonAz · 03-15-2022, 08:52 AM

Lt Dan, Did you put the gray tank flush on the passenger side?

bneumann · 03-17-2022, 05:18 AM

Corroborated info with Tiffin & they agreed:

- Remove basement fixed panel in front of rear ps tire
- could be sensor fallen off outside tank wall, or bad sensor, or crud inside tank
- grey tank is larger of two black colored tanks

Will look at this weekend.

Also wondering how & how easy it was to install a water connection to flush the grey tank ? If not too hard maybe will try as well, if required.

brandss · 03-17-2022, 06:01 AM

Like Lt Dan I too added a rotating cleaning head to the grey tank. I run it along with the black tank once a month or so. Since I've added this and flush the tanks I get perfect readings all the time.

I know some think it's foolish to worry about the tanks and the readings, and they have their methods that work for them. We full time and it makes it a lot easier to read the tanks. I also added a red LED light, mounted on the bottom of the cabinet where we check the tank levels, and it turns "red" once any of the tanks get to 90%. That too, is a great upgrade and we never really check tank levels.

bneumann · 03-18-2022, 05:51 AM

Would it be possible to share info on details of what exactly done to add water flush to grey tank.

Locations may be different for some models eq. RED vs Bus but concept location may be similar. If photos available all the better.

Thanks

**Lt Dan** · 03-18-2022, 06:39 AM

When I had the panel off to add SeeLevel sensors to my tanks, I added the flush sprayer on the same end of the tank as the black tank sprayer. That way, it has the full length of the tank to flush since it's opposite the drain. I ran a hose across to the other side, drilled a hole in the wet bay panel and installed a second hose connection next to the black tank cleanout. Since the hose is running downhill from the connection to the sprayer, there was no reason to install a check valve or vacuum breaker.

bneumann · 03-20-2022, 06:08 AM

Removed the fixed basement panel where the manual fresh water inlet is & found all in good order.

Additional items found:

- rusted machine bolt, some loose wiring & a spare hose connector
- also found mismatched rusted self-tap screws holding panel brackets to body
- one Robertson head 1 1/2 inches the other 3 Phillips head 3/4 inches
- one of the 3/4 Phillips screws snapped when removing, so now have to drill out or add a new location screw.

It's always an adventure when gaining access to something hidden in a motorhome. I suspect someone at the Canadian dealership must have fooled around in there since the odd screw is a Robertson which I think is still banned for sale in the US (usually use Phillips head instead.)

Anyways now using stainless steel replacement screws & will have to try to remove the snapped screw out when back home.

Getting side tracked by poor workmanship issues is very common when
trying to fix things in a motorhome. The initial false grey tank reading issue is still not solved; now will try 1/2 grey water tank full of fresh water with Dawn & some Calgon & let it slosh around on the drive home. Maybe that will clear slop off the inside grey tank walls enabling sensors to get clear readings or maybe get SEE Level sensors installed along with a flush on the grey tank.

There is always something else.

Mongobird · 03-29-2022, 04:54 PM

Quote:

Originally Posted by bneumann

Removed the fixed basement panel where the manual fresh water inlet is & found all in good order.
...

Getting side tracked by poor workmanship issues is very common when
trying to fix things in a motorhome. The initial false grey tank reading issue is still not solved; now will try 1/2 grey water tank full of fresh water with Dawn & some Calgon & let it slosh around on the drive home. Maybe that will clear slop off the inside grey tank walls enabling sensors to get clear readings or maybe get SEE Level sensors installed along with a flush on the grey tank.

There is always something else.

Not sure the Calgon is needed. I use a low cost detergent (Broadwalk I think) and about 3/4 of an oz. of that plus Dawn works well. The two different surfactants do a pretty good job of softening the goo. Just an idea. Probably cheaper than the Calgon as well. Salts are also used in the laundry detergent, and help as well.

For my ultrasound for parts washing, I just use the laundry detergent. About a tablespoon for 3L of water works for almost any think, except some greases.

Marshalone · 03-30-2022, 06:25 AM

I have had this problem with all 3 of my RVs including my 2018 Jayco Precept. The main black water tank almost never reads empty and the rear black water tank is not quite as much work to get it to empty. If I bring the 'tool' in that the hose hooks up to and it sends a high pressure rotating water spray around inside the tank I can usually get it down to read empty. Suggests to me that something (?) sticks to the sensors to create this false reading. Pain in the rear end however this is something we just have to live with I guess. Happy camping.

okcnewbie · 03-30-2022, 06:43 AM

I have the KIB system and this may not be applicable to the OP.

On my system the outside monitor panel seemed to read closer than the inside panel. The inside panel didn't seem to change much at all. I swapped panels and the problem moved showing me that one of my panels was bad. I also found out while troubleshooting that I was able to test wiring by disconnecting the ground on each tank and shorting it to the other three wires one at a time.
Unltimately, a new monitor panel fixed my problem.