Non-Pressurized Tanks

All water tanks Class A Customs carries must be vented, they are not pressurized tanks.

Have a certified technician install all parts to prevent product damage and personal injury.

Tank must have a large enough opening for air to freely move in and out of tank, this is called "venting" the tank.

If tank is not properly vented tank will explode when filled or implode when emptied.

A garden hose is a pressurized water line, do not make a secured connection to the water tank with a pressurized line.

Tanks need to be gravity feed, this allows for air to escape while the water is going into the tank.

What is a fill dish?

The fill dish is located on the outside of your unit so that you can easily add water to your fresh water tank without the need of opening a compartment or climbing under your unit. The fills dish also includes a small vent that allows you to connect your water tank vent to the outside of the unit, if your tank overflows it will overflow outside your unit. You can find the fill dishes in the Plumbing Category.

For adding water to the Fresh / Gray Water Tank you need a Gravity Fill Dish
the food safe garden hose rests in the fill port on the fill dish - it does not screw onto the port
this is a non-pressurized fill

For using water directly from a food safe garden hose you need a City Fill Dish
The plumbing will bypass your water tank and hook directly to your water heater and faucets.
The food safe garden hose makes a sealed connection on the fill dish and the water supply is pressurized.
This is a pressurized line and can NOT hook to your water tank - pressurizing the tank will cause the tank to explode, fittings to pop-out, cracks to tank, etc.
Units that have metal water tanks can use city fill dishes because the metal tank can withstand the pressure, Class A Customs water tanks can not be pressurized.

We carry Gravity Fill-Dishes, City Fill-Dishes and Combo Fill-Dishes that have both gravity and city, the benefit of having both is you can have a water tank of fresh water but if you go to a location that supplies pressurized water (campground - fair - etc.) you do not need to use your water tank supply of water you can simply use the water provided. Be sure to look at the provided example plumbing diagram for more reference.

How do I get water from the fill dish to the water tank?

How do I vent the tank?
Do you have plumbing for this?
Designed for Class A Customs Stock Fresh Water Tank set-up using a Fill Dish (fill dish not included)
This is for Fresh Water Systems Only - Not to be used for Gray or Waste Water Systems
Kit does not fit a SPOUTED Water Tank

For my application I am not using a fill dish.

You can place a larger fitting such as a PVC elbow into the per-installed tank fitting and just rest the garden hose in this fitting, Do not make a secured/sealed connection as this would then be pressurized and would damage the tank. This would then be a gravity fed fill, you can make the same type of fitting set-up for your vent.

  • Be sure to have an additional fitting open at the top of the tank to let air in/out when using the tank, this would be your vent.
  • You can cap the fitting (a) and vent (b) when transporting to prevent water from spilling.
  • Be sure to uncap the vent when removing or adding water to the tank.
  • It is best to have a screen over the vent fitting to prevent anything from entering the tank.

Can I use a water pump with the water tank if it in not in an RV?

Can I use a pressure washer with the tank?

Using a water pump or pressure washer with the tank pressurizes the water line after the water pump or pressure washer it does not pressurize the water tank.

You must vent the tank to allow air in and out during use.

Examples of Plumbing Set-ups

You will need to verify your needs and set-up, these are examples only, we build our water tanks but do not install them in these different applications.

Coffee Cart Set-up

Espresso Machine Plumbing Set-up

Mobile Bar Set-up


Class A Customs Fresh and Gray Water Tank Installed Fittings

Class A Customs only installs the following fittings into our Fresh / Gray tanks at this time
1.5" NPT Female - fitting is closed
.5" NPT Female - fitting is open
1.25" Outer Diameter x 2" Long Smooth Pipe / Boss Fitting - Spout

1.5" NPT Female - fitting is closed
use a razor knife to cut membrane out, easiest when cut in halves

Fittings and Hoses We Offer That Fit 1.5" NPT Tank Fitting

Can be used with 1.5" Fitting on tank to connect to 1.375" Hose

Can be used with 1.5" Fitting on tank to connect 1.5" PVC Pipe for draining fresh or gray water tank

1.375" (1-3/8") Food Grade Water Hose
1.375" hose can be used with the fill dishes and the Loose Fitting / Fixture - 1.5" Thread x 1.25" Hose Barb Fitting - Gray
1.375" hose can not be used with spouts on tanks.

.5" NPT Female - fitting is open

Fittings and Hoses We Offer That Fit .5" Tank Fitting

Can be used with .5" Fitting on tank with .5" Hose for Fill Dish Vents and Water Pumps

.5" Hose can be used with the fill dishes vents and the water pumps we sell.

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