Class A Customs Plumbing Example


This is an Example of plumbing for a trailer, you will need to verify your configuration for your unit.

All water tanks we carry must be vented, they are not pressurized tanks, allow air to move in and out when filling and emptying the tank. Do NOT fill the tank directly from a pressurized line (garden hose), this is not a safe option and will explode 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 tank without the need of opening a compartment or climbing under your unit. You can find the fill dishes in the Plumbing Category.


For adding water to the Water Tank you need a Gravity Fill Dish, the hose rests in the port it does not screw onto the port this allows you to place a garden hose into the Gravity Fill Dish port without making a sealed connection so the supply is not pressurized.


For using Water Directly from a garden hose you need a City Fill Dish, the hose makes a sealed connection and the water supply is pressurized, you can not hook this to your water tank and you do not need to go through your water pump.


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.


Fill Dish - Look In Plumbing Category
Fill Dish Can Be Found In Plumbing Category

I am not using a fill dish how can I fill the tank?

We recommend you place a fitting in the tank that will allow you to rest the hose in to fill, not make a sealed connection, you can then cap this when not in use. You can use an elbow fitting to allow you the fill the tank to capacity, use an elbow with a screen secured over it to vent the tank.


How can I vent the gray tank?
You can run a pipe or hose to the outside of your unit, even the underside, and cover it with a screen to prevent anything entering. Some health departments require you to vent out the top of your unit the same as a house vent, for this you would need to run a pipe up through the roof and cover with a plumbing cap, this is also the method a Black Waste Tank uses.

Heng's Plumbing Cap
Plumbing Cap Can Be Found In Plumbing Category