Holding Tanks - When do they blow?

[grotto69]

2nd trip in our new FR3. Newbie RV'er.

When the grey water tanks says 2/3's full.... Is that the top of 2/3 or the bottom.

How many gallons is 2/3's on the display at the control center.

We unhook tomorrow, should be okay, but want to understand better how it works.

Grotto

[Brother Les]

Originally Posted by grotto69

2nd trip in our new FR3. Newbie RV'er.

When the grey water tanks says 2/3's full.... Is that the top of 2/3 or the bottom.

How many gallons is 2/3's on the display at the control center.

We unhook tomorrow, should be okay, but want to understand better how it works.

Grotto

You know that your gray holding tank is full when water comes up out of the tub drain. ...

Does your light tree not have 4 lights on it? Seems like my first one is always lit. The second one comes one after 2 or 3 sink full of dishes being done. I don't think that would fill up half of the gray water tank. I think the 3rd light (out of 4) comes on about a little over the half way filling of the tank. The 4th light comes on with 3 or 4 gallons of room left (imo). Leave the 4th light on the tree too long and using more water..... up the drain and into the tub it goes......

[OldCoot]

To alleviate your fears, #1 they don't BLOW. They may leak or rupture, but they don't BLOW. They are full and need emptying when the 3rd light out of 4 lights light. No real harm if you wait until the 4th light shows. Don't worry, you'll know when to empty by other methods beside the lights.

[rburns4147]

The tank sensors are notorious for not being accurate. What is 2/3 of a tank on your RV might not be the same 2/3 on someone else's RV. Mathematically, if you had a 40 gallon gray tank and your sensor just switched over to 2/3, you should have 26 gallons in the tank. But in the real world it may not work out that way. After a few uses you should be able to tell when your tanks are almost full.

[AquaMan]

After 2yrs of owning this 5er, I checked the tanks for the first time this weekend. I was bored. I know we can 4-5 days easily on our tanks (2blk - 3 gry). When i emptied I was at the 3/4 mark on 1 blk and the shower tank. Other tanks are at 1/2 at most.

[OldCoot]

Originally Posted by AquaMan

After 2yrs of owning this 5er, I checked the tanks for the first time this weekend...

I believe that's a record!!!

[AquaMan]

Just to clarify for OC, it was the first time for "checking" the monitor, not for "emptying".

[BamaBob]

Originally Posted by grotto69

2nd trip in our new FR3. Newbie RV'er.

When the grey water tanks says 2/3's full.... Is that the top of 2/3 or the bottom.

How many gallons is 2/3's on the display at the control center.

We unhook tomorrow, should be okay, but want to understand better how it works.

Grotto

Grotto,

Since you say you are new, these holding tank rules may bear repeating:

• If you are hooked up to a camp sewer, never leave your grey or black water drains open (bad things will happen )
• When dumping, let the black water drain rip first.
• Once the black is done, flush your sewer line with the contents of the grey water tank.

[OldCoot]

Originally Posted by AquaMan

Just to clarify for OC, it was the first time for "checking" the monitor, not for "emptying".

Ya had me worried Timmy.

[Brother Les]

Originally Posted by OldCoot

Ya had me worried Timmy.

His user name is "AquaMan".... after all......

[BamaBob]

Originally Posted by Brother Les

His user name is "AquaMan".... after all......

OH, that is TOOOOO Funny!!!

[AquaMan]

You dudes are killing me! lol. As an FYI, my site here in FL has been dry since the rain stopped Saturday afternoon!

[parpar1]

Originally Posted by grotto69

2nd trip in our new FR3. Newbie RV'er.

When the grey water tanks says 2/3's full.... Is that the top of 2/3 or the bottom.

How many gallons is 2/3's on the display at the control center.

We unhook tomorrow, should be okay, but want to understand better how it works.

Grotto

i would say it is right at 2/3s s said before. Just like a measuring cup. a 1/2 is a 1/2. So 2/3s is 2/3's. so if it is a 20gal tank there is 13.33 gal of waste. A 30 gal tank there is 20 gal. 40 gal tank there is 26.6 gal waste.

[grotto69]

Thanks everyone for the great comments. I learned a lot and had some good laughs too.

[BarbaraG]

One thing I've found is that the gray and black tank sensors often read higher than they should. I'm told this is because the sensors can get blocked (don't want to think about by what...). I don't think they ever read lower than they should, which is good.

I've been living in my 30 DS for six months now and have found that with normal usage (on city water so not being super conservative) I need to dump the gray water tank about once a week (there's just me), sometimes more frequently. I generally dump the black at the same time; black first gray second as per recommendations. Twice I've pushed it a little too long and had a little water coming up in the shower.

Barbara
2014 30 DS FR3

[Witch Doctor]

Originally Posted by HSVBamaBob

Grotto,

Since you say you are new, these holding tank rules may bear repeating:

• If you are hooked up to a camp sewer, never leave your grey or black water drains open (bad things will happen )
• When dumping, let the black water drain rip first.
• Once the black is done, flush your sewer line with the contents of the grey water tank.

Please tell me why you should not leave your gray water tank open hooked to a sewer? I understand about the black tank, but the gray water I would like to here your reason behind that myth. This should be good... who made up these rules that you quoted?

[OldCoot]

Originally Posted by gljurczyk

Please tell me why you should not leave your gray water tank open hooked to a sewer? I understand about the black tank, but the gray water I would like to here your reason behind that myth. This should be good... who made up these rules that you quoted?

Third in the list explains why to not leave the grey tanks open.

[Batts-toy]

Originally Posted by gljurczyk

Please tell me why you should not leave your gray water tank open hooked to a sewer? I understand about the black tank, but the gray water I would like to here your reason behind that myth. This should be good... who made up these rules that you quoted?

I leave it open until the last day of camping then close it so some grey water will accumulate for Black water drain follow up.

[BigTJohn]

Tanks should be at least 2/3s full for adequate pressure and volume for max flow rate when valve is opened. (you did attach the hose, right?) Then blk 1st let it realyy drain well, back flush if possible, then close it and do the other grey tank(s) galley then bath going from dirtiest to cleanest, relatively. I black tank is left open, then no liquid is present for bacteria breakdown of solids and the brown cement left takes many months to soften and lots of work to get it out.

[mjones12]

Originally Posted by gljurczyk

Please tell me why you should not leave your gray water tank open hooked to a sewer? I understand about the black tank, but the gray water I would like to here your reason behind that myth. This should be good... who made up these rules that you quoted?

I always leave the gray open when hooked to sewer system.