Fresh water tank not emptying completely.

[ncitro]

ncitro
Hi Neil,
I think the upper loop is an (ineffective) attempt to control the surge pumping overflow.

Rob

Makes sense I guess. I am seriously toying with an upgrade. I found Icon sells the tanks with the sump, they are not cheap, but we boondock a fair bit and the extra water would be really nice. Obviously there is the weight to consider, but with that big of a tank we would fill close to the destination.

[ncitro]

Cate&Rob Guest I did an experiment today and ran my pump until it sputtered. Then I emptied into a bucket and got only a couple of gallons, so either I have the sump (need to bite the bullet and drop the rear coroplast, or something is engineered differently in my tank that allows it to get more water out. Rig was level, so not tipped to the side at all.

[Guest]

Cate&Rob Guest I did an experiment today and ran my pump until it sputtered. Then I emptied into a bucket and got only a couple of gallons, so either I have the sump (need to bite the bullet and drop the rear coroplast, or something is engineered differently in my tank that allows it to get more water out. Rig was level, so not tipped to the side at all.

Nice,

For now I have to assume I have a 42 gallon tank rather than 52 gallons. I keep two 6 gallon water jugs in my rig along with a folding hand truck and have to add those after 4 days.

Jim

[chrisopy]

Just returned from a trip where the water pump had been pulling air prior to traveling back home. Once at home, and using a 5 gallon bucket I measured approximately 10 gallons of water from the tank drain on my 2600RB.

Jim

So the pump was sucking air while it was off and you were traveling?

[Guest]

So the pump was sucking air while it was off and you were traveling?

chrisopy ,

It was beginning to suck in air while turned on and in use at the campsite. I turned off the pump and we packed up and traveled home.

It was when we were home that I performed the bucket drain test to see how much water was still in the tank. It seems the older units like mine have a pickup tube that is above the floor of the tank.

Jim

[howson]

Just returned from a trip where the water pump had been pulling air prior to traveling back home. Once at home, and using a 5 gallon bucket I measured approximately 10 gallons of water from the tank drain on my 2600RB.

Jim

Something is definitely not right. I measured what came out of my 315's tank after the pump stopped sending water to the bathroom faucet and the total is 48oz.



I poured the water that was in the bucket into a bottle that had measurement marks, so I know the total is 48 oz. (I waited until water stopped coming out of the drain.)

Nothing I recently did changed the fresh water tank setup--it's been my experience on many occasions to only have a small amount of water left in the tank when the pump stopped working (but I'd never measured it).

[howson]

Cate&Rob ,
In post 14 you reference a "sump tank". So Jim's tank is different from mine (shown below)?

10 gallons is an awful lot to be left in the tank.



Howard

[Cate&Rob]

howson
Hi Howard,
The picture attached to post 10, more clearly shows the small "sump" (now known to be 48 oz ) at the bottom of the tank where your water pick-up line is attached. I have not pulled this section of coroplast on my Reflection, but I know that there are still several gallons of water in my tank when the pump starts drawing air. JimGuest has reported the same thing, so we must have tanks where the pickup is higher than the bottom of the tank. As mentioned earlier, this is a relatively normal way to plumb a water tank to avoid drawing sediment into the pump. Unfortunately it also means that we are are carrying around water that we can't use.

Rob

[ncitro]

howson
Hi Howard,
The picture attached to post 10, more clearly shows the small "sump" (now known to be 48 oz ) at the bottom of the tank where your water pick-up line is attached. I have not pulled this section of coroplast on my Reflection, but I know that there are still several gallons of water in my tank when the pump starts drawing air. JimGuest has reported the same thing, so we must have tanks where the pickup is higher than the bottom of the tank. As mentioned earlier, this is a relatively normal way to plumb a water tank to avoid drawing sediment into the pump. Unfortunately it also means that we are are carrying around water that we can't use.

Rob

I’ve dropped mine and I do have the sump. I get less than a gallon after my pump starts sputtering.

[howson]

Cate&Rob and ncitro -- that explains it. Good pic, too, showing the sump.

[Guest]

What would a new style water tank cost?

Without pulling the coroplast I'm wondering if we can do some plumbing mods and tee off the drain line to feed the pump?

10 gallons of water I cannot use is really wasteful.

Jim

[howson]

What would a new style water tank cost?

Without pulling the coroplast I'm wondering if we can do some plumbing mods and tee off the drain line to feed the pump?

10 gallons of water I cannot use is really wasteful.

Jim

The drain line is higher than the output line, Jim. (That won't help!)

[Guest]

The drain line is higher than the output line, Jim. (That won't help!)

Howard,

I believe in my case the drain must be lower than the output line to the pump or I would not be able to drain off the 10 gallons. Is there a pic of the old style tank?

My drain is not like yours with the gate valve.

Jim

[Cate&Rob]

Guesthowson Floyd&Tamily

Hi Jim,

This parallel post https://gdrvowners.com/forum/operati...king-air/page2, particularly the scope pictures attached to post 23, have me wondering if we have some sort of contamination effect going on that is preventing drawing out the last few gallons of water. I guess one or the other or both of us are going to have to pull down the coroplast and take a look . I have "assumed" that the pick-up in my early build Reflection is above the bottom of the tank because of the way it behaves. I have never seen an actual picture of this. Your trailer is a much later build . . . it is difficult to imagine (no pun intended ) that Grand Design would use different configuration water tanks across different products, at the same time.

Rob

[howson]

Howard,

I believe in my case the drain must be lower than the output line to the pump or I would not be able to drain off the 10 gallons. Is there a pic of the old style tank?

My drain is not like yours with the gate valve.

Jim

I was thinking of the overflow line--my bad!