Fresh Water Tank Capacity 297RSTS 2021

[PineconeNW]

If the water tank is 36" x 60" and the vent port is 1" below the top, you would lose about 9 gallons. 54 - 9 = 45.

I just read through the thread again and I think I missed this post.
The vent is on the side and your math explains the issue.
Thank you.

[DavidBarnes792]

I understand that we lose a few gallons bc of the overflow, but this is ridiculous... I own an Imagine XLS 22MLE and discovered today that the 47 gallon fresh water tank will only hold 31 gallons. 16 gallons short of the stated capacity?? If any other members have the same model I am interested to know if this is normal for the 47 gallon tank.

[Country Campers]

I understand that we lose a few gallons bc of the overflow, but this is ridiculous... I own an Imagine XLS 22MLE and discovered today that the 47 gallon fresh water tank will only hold 31 gallons. 16 gallons short of the stated capacity?? If any other members have the same model I am interested to know if this is normal for the 47 gallon tank.

If you are filling the tank until it water comes out of the overflow tube then it will cause a syphoning effect that will drain your tank to some kind of level until it quits. The manuals state to fill until the tank sensors say it is full and then stop filling, this will leave about a 1" air gap at the top of the tank and should not introduce the syphoning effect. Some owners have installed a shut off valve on the overflow tube to be able to fill the tank full and not lose any water to the syphoning effect, do this at your own risk as there is plenty risk involved.

Brian

[howson]

I understand that we lose a few gallons bc of the overflow, but this is ridiculous... I own an Imagine XLS 22MLE and discovered today that the 47 gallon fresh water tank will only hold 31 gallons. 16 gallons short of the stated capacity?? If any other members have the same model I am interested to know if this is normal for the 47 gallon tank.

The specs on the 22MLE on Grand Design's website shows 43 gallons. https://www.granddesignrv.com/showro...ns/22mle#specs

The fresh water tank itself has a capacity of 37 gallons (according to information I can access as a moderator). The difference (6 gallons) historically was because of the water heater capacity. With today's tankless (if that's what your Imagine has) then there's no extra 6 gallons. If there's a traditional water heater, then you will have the extra 6 gallons, or 43 total.

That your Imagine holds 31 gallons instead of 37 gallons (I assume you had a meter of some sort) is not terribly unusual. Due to the vent and overflow there is some "head room" in the tank that won't get filled.

BTW--welcome to the forum, David.

Howard

[DavidBarnes792]

Thank you for the feedback. Yes, I used a "hose end" meter to measure the capacity of the fresh water tank. I checked the acuracy of the meter and it's right on. I do have a tank style water heater so I suppose I have to add that 6 gallons to the capacity, which is still only 37. I will use the fresh water tank until it runs dry and just carry a couple of jerry cans as a backup. Adapt and overcome.