Gray water tanks

[BillinTexas]

Our 221RB has two gray water drains so I assume there are two tanks. Perhaps I'm assuming wrong. I would like to know if this is the case and if so, how many gallons is each tank. I only see specs for the total. Does anyone have the answer?

[howson]

Our 221RB has two gray water drains so I assume there are two tanks. Perhaps I'm assuming wrong. I would like to know if this is the case and if so, how many gallons is each tank. I only see specs for the total. Does anyone have the answer?

Yes, you have two gray tanks. A 29 gallon for the kitchen and a 39 gallon in the bathroom.

Actual capacity may be slightly less due to installation of venting, pipes, etc.

[TucsonJim]

Good morning Bill. I took a look at the 221RB drawings, parts look-up and specifications. Indeed, you're Transcend has two gray holding tanks. The rear tank is 39 gallons and drains the bathroom sink and shower. The front gray tank is for the kitchen sink and is 29 gallons. I cross referenced this by looking up the holding tank parts on the GDRV parts lookup page.

GDRV-Emily


On the GDRV 221RB Transcend page, it shows "Grey Capacity as 79 gallons". According to the DWV drawing (Revision Date 12/12/18), the combined gray capacity is 69 gallons, not 79. A correction is probably needed to either the specifications on the web page, or the drawing needs to be updated if there has been a change.

Jim

[BillinTexas]

Yes, you have two gray tanks. A 29 gallon for the kitchen and a 39 gallon in the bathroom.

Actual capacity may be slightly less due to installation of venting, pipes, etc.

Thank you, Howard. I thought I had seen the amount somewhere but was mistaken. I see from Jim's post that the actual combined capacity is less than shown on the website.

Good morning Bill. I took a look at the 221RB drawings, parts look-up and specifications. Indeed, you're Transcend has two gray holding tanks. The rear tank is 39 gallons and drains the bathroom sink and shower. The front gray tank is for the kitchen sink and is 29 gallons. I cross referenced this by looking up the holding tank parts on the GDRV parts lookup page.

GDRV-Emily


On the GDRV 221RB Transcend page, it shows "Grey Capacity as 79 gallons". According to the DWV drawing (Revision Date 12/12/18), the combined gray capacity is 69 gallons, not 79. A correction is probably needed to either the specifications on the web page, or the drawing needs to be updated if there has been a change.

Jim

Jim, thank you for this information. Possibly a typo on the web page? The information will help us with tank management.

[BillinTexas]

Readying for an upcoming trip a question came to me about these tanks. Which is tank 1, the bath, or the kitchen? Thanks.

Also, how are the tank sensors set up inside the tanks? High, low?

[howson]

Readying for an upcoming trip a question came to me about these tanks. Which is tank 1, the bath, or the kitchen? Thanks.

Also, how are the tank sensors set up inside the tanks? High, low?

By "tank 1" I assume you mean the label on the Convenience Center? The only way to know for sure is to add water to one of them and see which indicator corresponds.

The sensors are "stacked" on the side of the tank: low, medium and high. You can see them on this shot of a gray tank:

[BillinTexas]

Howard, thank you. This is part of my tank management training as we stay at campgrounds many times that don't have site sewer and only dump stations.

[Cate&Rob]

BillinTexas howson

To add to Howard's description, attached is another view of the tank probes. I don't know what the "?" probe is . . . it looks to me like they moved the ground probe away from the others. All my tanks are the same. It is important to understand that these tank level monitoring systems are notorious for being inaccurate. In my experience, the indicated level is wrong more often than it is right.

WRT which handle is for which tank . . . when the bundle of cables arrive at the handle location during manufacturing, they do not always get installed in the same order, so even two trailers of the same model can have the pull cables in a different order. Best to put water in one tank and then pull each handle individually to see which one drains the water, as Howard describes.

Rob

[Canyonlight]

Rob Cate&Rob - I seems to recall that some or all of our prior RVs had sensors that read out (in addition to "E" like we now have) 1/4, 1/2. 3/4. and full (4/4). This may explain the lowest sensor being the 1/4 measure used when RVs are built with 4 reading levels plus empty, rather than 3 levels we now have. I have always wondered why our readings seem inaccurate at the 2/3 and 1/3 readings. Maybe this is why.....hmm ?

Dan

[Cate&Rob]

Canyonlight
Hi Dan,

When I look at the physical spacing of the probes on a basically rectangular tank, it looks to me like the lowest connection (with the green wire) should be on the ? probe. Then the three "thirds" would be more-or-less evenly spaced.

When we first got our Reflection, I tried to get the tank indicator lights to function correctly. Various tank washing and flushing scenarios. I realized that even if I got them to read correctly, a week later they would be wrong again. So I gave up (better for my blood pressure ) . . . I can't even remember the last time I pushed the "level indicator" buttons, it was years ago.

Rob

[BillinTexas]

BillinTexas howson

To add to Howard's description, attached is another view of the tank probes. I don't know what the "?" probe is . . . it looks to me like they moved the ground probe away from the others. All my tanks are the same. It is important to understand that these tank level monitoring systems are notorious for being inaccurate. In my experience, the indicated level is wrong more often than it is right.

WRT which handle is for which tank . . . when the bundle of cables arrive at the handle location during manufacturing, they do not always get installed in the same order, so even two trailers of the same model can have the pull cables in a different order. Best to put water in one tank and then pull each handle individually to see which one drains the water, as Howard describes.

Rob

Thanks, Rob. I will give the two gray tanks a test when I arrive back home from a warranty appointment trip we are leaving on tomorrow. Getting the board in our Norcold replaced so it will run on propane. Was bad when we took delivery.

[BillinTexas]

Is the full sensor a little below the actual top of the tank? This on the black tank. The photo makes it appear so. Trying to get another 24 his without having to dump. Thanks.

[howson]

Is the full sensor a little below the actual top of the tank? This on the black tank. The photo makes it appear so. Trying to get another 24 his without having to dump. Thanks.

You're drive yourself bonkers if you try to rely on the sensors, BillinTexas . As Cate&Rob already described the sensors are notoriously inaccurate.

When the potty "burps" (you'll know it when you hear it) it's time to dump.

[JBill9694]

Is the full sensor a little below the actual top of the tank? This on the black tank. The photo makes it appear so. Trying to get another 24 his without having to dump. Thanks.

I have delayed dumping the black tank when the sensor reads 100% (Yes I know the sensor is not accurate, but I can still get it to read between 66% and 100% full so I might as well use it) because we got back too late for me to do my dump, flush, and prime routine with no adverse effect. As howson indicates, the tank is not full until to toilet burps and our sensor indicates 100% before this happens,

[BillinTexas]

Thanks for the replies, Howard and John. We do use ours as an "indication" of how much is in the tanks. I have experimented at home enough to feel comfortable with what the levels are telling me. With gray only of course. We were in 5 days and 4 nights last week and the last day used the state park facilities when we could. We never hit full. I have since purchased and portable tank for extended trips.