Grey Water Monitor Calibration

[DavidS]

We have had our Oliver only since last September, and many of the RV systems are new to us. One issue is the Grey Tank. We take one short shower and wash a few dishes and the Grey Tank is half full. Since we were camping at a State Park with full hookups, I decided to do an experiment to test the calibration of the Grey Water Monitor.

 

I did the experiment with the trailer completely level. I emptied the Grey Tanks, and the Monitor read 13. I then filled a 5 gallon bucket with water and poured it into the shower drain. Monitor reads 44! Only 5 gallons, and it reads 44! Pour another five gallons into the drain, record the monitor. Repeat. When I had poured 25 gallons into the system the monitor read 100. I could only pour about 3 more gallons into the drain before the tank was full and water backed up into the shower pan. Thus the total amount of water I could add was 28 gallons. Since the Oliver Grey Tank has a 35.5 gallon capacity, I assume that the tank was not fully drained, and it still had 7.5 gallons still in the tank at the start of the experiment.

 

 

So I am not crazy. We add five gallons to the (nearly) empty Grey Tank, and the Monitor reads 44, but it is only 35% full.

 

I did this experiment with the trailer level, because the trailer is level when I Monitor Grey Tank usage. I have noticed that when I empty the Grey Tanks with the nose elevated, the Monitor reads zero, but whenever I empty with the trailer level, the Monitor reads 13. Lesson: Empty tanks with nose elevated…

 

Lesson two: I do not need to panic if the Monitor reads 80, it is only 2/3 full.

 

My experiment is not perfect. I used a line on my bucket as the 5 gallon mark, and that may not be completely accurate. I could repeat the experiment with the tank fully emptied, but my wife already gave me grief about wasting 30 gallons of fresh water.

 

My questions: Have others experienced this problem? Is there an easy fix, short of a 1650 mile drive to Hohenwald?

 

Finally, we camped at Kodachrome Basin State Park, which was lovely. Highly recommended. They take reservations at the campground, and we reserved a site with hookups. 15 of the 34 sites have hookups. The site we had with hookups was really nice. But if we go again I would reserve one of the non-hookup sites on the edge of the campground. These sites are very pretty and really private.

 

David

 

 

[Trojans1]

I have the same problem. When I can I lift the hitch to get a gravity flow and I have also tried to have the monitor clean from various suggested additives. I have learned to live with it and now just keep an I on usage. When we both shower I tend to empty it.

 

 

[KarenLukens]

Mine was at 13 also, now it empties to zero when level. The fix with pics is here towards the bottom of pg1 -

 

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http://olivertraveltrailers.com/topic/reed-karens-blog/

[SeaDawg]

Out of curiosity, did you check your freshwater levels? Grey and fresh in our trailer are about the same. If fresh is empty, grey is nearly full.

Our trailer is older, but we always jack the front at the dump station. You won't get everything out without a bit of rise, with the flatter, rectangular tanks. Rise helps with the black, too.. though it is a more ordinary, more square style.

Level side to side can also present an issue. But, you can jack the front up a lot, on the hitch, and deal with that. To eliminate drainage "spill" issues, a lot of dumpsites pitch to the drain. Quite reasonably.

Sherry

[KarenLukens]

I was wrong, did it tonight again and it empties to 6% now on level. It started at 25% with the rise in the hose, then 13% quickly, but if I leave it open it slowly drains down to the 6%. Then if I tilt it up just a bit, it goes down to 0%.

 

We usually get 1 1/2 to 2 fresh tanks to one full gray but we are cooking with, cleaning and drinking the water also.

 

It would be nice to have a large black tank option like theBigfoots.

[geO]

What an EXCELLENT idea Dave! I will do this next time I'm at a full hook up site.

[SeaDawg]

Dave, if Oliver ever does a calendar, that photo of your rig and the scenery should be in it. So beautiful!

Sherry

[KarenLukens]

It's nice to have numbers for the levels, but being that the tanks are set on blocks to give them a bit of tilt, the percentage will be off by quite a bit. Since you already have your bucket set up, after you tilt and dump some time maybe then add 3 1/2 buckets and see what the number is for the half tank, I've tried and ours reads 75% at about half full. This would give us a close measured half tank value. Also because of the angle of the tank, it reads 100% full long before the water comes out of the overflow. You can't get an accurate tank reading gauge with the flat tanks that we have being tilted a bit because the inputs would have to placed on both the high side by the bathroom for full and down at the low side by the rear bumper for empty . So I just don't go by the numbers. We know that the tank is 100% full when the water comes out the overflow :)

[BlaiddDrwg]

Comparing the 2017 sales brochure to the 2018 brochure revealed a difference in capacities for both the Fresh and Grey water tanks.  The 2017 sales brochure says the Fresh Water Tank Capacity is 32.5 gal. and the Grey Water Tank Capacity is 35.5 gal.  The 2018 sales brochure says the Fresh Water Tank Capacity is approximately 30 gal. and the Grey Water Tank Capacity is approximately 30 gal.  I wonder if they changed the tanks or just updated the numbers to reflect usable capacities?

[topgun2]

 "I wonder if they changed the tanks or just updated the numbers to reflect usable capacities?"

 

Perhaps the lawyers got involved?

 

Bill

 

 

[DavidS]

Last September I noted the discrepancy that BlaiddDrwg referred to, and I wrote the following to Jason Essary.

 

Hi Jason,

I have a 2016 Oliver Elite II, Hull 164.

I have a question about the grey water tanks. On page 47 of my Oliver Owner’s Manual, it says that the grey water tank holds 35.5 gallons, and on page 45 it says the fresh water tank has a 32.5 gallon capacity. It has these same tank volumes on the brochure you sent before I purchased.

On your web site, you have conflicting information about tank size.

http://olivertraveltrailers.com/trailers/legacy-elite-2/

In the ELITELY EQUIPPED STANDARD FEATURES section it says

32.5 Gal. Large Capacity Fresh Water Tank

35.5 Gal. Large Capacity Grey Water Tank

However at the bottom of the page in the LEGACY ELITE II SPECIFICATIONS section it says

Fresh Water Tank Capacity 30 gallons

Grey Water Tank Capacity 30 gallons

Which is correct for the grey tank? 35.5 gallons or 30 gallons?

I have had problems with the accuracy of my grey tank monitor: See http://olivertraveltrailers.com/topic/grey-water-monitor-calibration/

If the grey tank is only 30 gallons, that would affect my calculations.

Thanks,

David

 

I ended up talking to Jason on the phone, so I do not have his exact reply, but it was essentially that the lower numbers reflect the usable capacities.

 

BTW, the web site still has these discrepant numbers on tank capacity:

 

 

 

I updated my calculations and the graph showing Monitor Reading vs. Water in Tank. The new graph has Percent Full on the X-axis, which is more useful than Water (gallons). It is also attached as a pdf, so others can print it out if they want to use it.

 

Grey-Tank-Chart.pdf

[SeaDawg]

Because the grey and fresh tanks are hoizontal, and not that tall, I think there will always be a bit of discrepancy in the readings. But, there are always discrepancies, as we've seen over the many years.

 

Last year, we calibrated the new holding tanks on our boat, very carefully measured, in the yard, before installation of the sensors. A number of times. We probably took a day and then some to try to get it right.

 

Even so, we'll not trust our calibration over 2/3. On a tack, less. Every little thing, and change in pitch front to back, side to side, makes a big difference in small tanks. Especially low, flat, horizontal tanks like the Oliver.

 

We've picked up brand new big RVs for delivery, and one single flush of the toilet registered a 1/4 tank.  But, I'd far rather have a premature signal than an overflow....

 

Sherry