Available in the Plumbing Category


Can I have the fittings moved?
Can you add extra fittings to the tank?
Class A Customs no longer offers custom fittings unless you are ordering 50 or more of the same tanks per order.
We offer Uniseal fittings that allow the end user to place a fitting anywhere in the tank. Installation video and sizes.
Search Uniseal in top search bar or look in Plumbing Category.

Question: What are the difference between the grommets and the Uniseals?
Answer: Grommets are not food safe so can only be used for gray or waste applications, the Uniseal fittings are food safe so can be used for all applications.

Uniseal® Pipe-to-Tank Seals

Uniseal® is the world's best seal, and installing it is a simple process. After cutting a hole in the wall of a tank or other surfaces, the seal is inserted. Then the pipe is coated with a slippery detergent and pushed into the seal. The Du Pont Alcryn® is the key to the liquid-tight seal. When the pipe is pushed through the rubber-like Uniseal® from the outside, the inside Alcryn® wall becomes thin enough to allow the pipe to squeeze through and then forms a liquid-tight seal. The coefficient of friction with the plastic pipe is roughly three times higher than any other material, which allows it to create a better seal than with any other material.

  • Alcryn® melt-processable rubber
  • Long-lasting
  • Resistant to acids, oils, greases, gasoline & sewage
  • Withstands pressure & suction
  • Withstands heat & cold
  • Easy installation
  • Reduced labor & material costs
  • In static conditions, the seal is good up to 65 psi

Uniseal®

Part No

Uniseal® Size

Sch 40 Pipe I.D.


Pipe O.D. Size *2


Holesaw Size Required



Imperial

Metric


Imperial

Metric


Imperial

Metric


U018

3/16"

4.75mm


0.250"

6mm


0.315"

8mm


U025

1/4"

6.5mm


0.375"

9.5mm


0.5"

12.7mm

*1

U0312

5/16"

8mm


0.40"

10.5mm


0.5"

12.7mm

*1

U038

3/8"

9.6mm


0.675"

17mm


1.0"

25.4mm


U050

1/2"

12.7mm


0.84"

21mm


1.25"

31.7mm

*1

U075

3/4"

19.2mm


1.050"

27mm


1.25"

31.7mm

*1

U100

1"

25.4mm


1.315"

33mm


1.75"

44.4mm


U125

1 1/4"

32mm


1.66"

42mm


2"

50.8mm


U150

1 1/2"

38mm


1.9"

48mm


2.5"

63.5mm


U200

2"

51mm


2.375"

60mm


3"

76.2mm


U275

2 3/4"

70mm


2.913"

74mm


4"

101.6mm

*1

U300

3"

76.2mm


3.5"

89mm


4"

101.6mm

*1

U400

4"

102mm


4.5"

114mm


5"

127mm

*1

U400-SDR35

4"

102mm


4.33"

110mm


5"

127mm

*1

*1 - Uniseals U025 and U0312, Uniseals U050 and U075, Uniseals U275 and U300, Uniseals U400 and U400-SDR35 require the same sizes of holes.

The difference is made up in the thickness of the Sarlink 4165 rubber.

*2 - Always measure the Outside Diameter (O.D.) of your pipe. This is the most important size to match into the Pipe O.D. hole size of the Uniseal to create your seal.


Instructions

1. Be sure to have recommended hole saw for selected fitting, check chart before cutting.
2. Using hole saw cut hole in wall, ensure that the hole is cut clean. Irregular holes could cause poor seating and possible leaks. File or sand the edges so there are no rough or sharp edges be sure to remove any remaining debris.
3. Insert the Uniseal with the wide surface facing out.
4. Make certain the pipe to be inserted is cut clean and square, file or sand the edges so there are no rough or sharp edges to cut the Uniseal surface.
5. Use liquid soap or Teflon lube on the pipe to be inserted. Insert the pipe into the Uniseal as far as needed to clear the inside of the seal by about 2".
6. Be sure to clean tank thoroughly prior to using removing any debris and lubricant residue.


EXAMPLE VIDEOS:
Videos are for educational purposes only, you will need to determine proper use for your application.














Blank Tanks
Blank Tanks mean no fittings are installed in tank. You will need to verify the lead time on Blank Tanks as we spin the fittings into our tanks as soon as they are made.
If we are currently making a tank we can get you a Blank Tank very quickly, shipping the next business day, however, if we are not currently making a tank it can take up-to several weeks to get a tank.
You can call or use the contact us form to ask about lead times on the Blank Tank you are needing.

When ordering a Blank Tank place the tank(s) you are needing in your cart and at check-out in Customer Comments specify what tanks are to be Blank:
EXAMPLE:
Part # is a BLANK TANK
All Tanks Are BLANK




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

For information on custom fittings or placements please use the Water Tank Build Form, please note this option is only available when order 50+ of a tank on single order.


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.



1.25" Outer Diameter x 2" Long Smooth Pipe / Boss Fitting - Spout
glues does not stick to pipe, it can not be sealed or capped
you will need to use the 1.25" Hose with Clamp




Hose We Offer That Fit 1.25" Tank Fitting
1.25" (1-1/4") Food Grade Water Hose
1.25 hose hose can be used with the gravity dishes and spouts/boss fittings on tanks.
1.25 hose does not fit the Loose Fitting / Fixture - 1.5" Thread x 1.25" Hose Barb Fitting - Gray






Where are the fittings located on the tanks?
Are there fittings on both ends of the tanks?

Please look at the photos of each tank as fitting placement can vary by tank, typically fittings are all located on one end of the tank.





How do I get the large fitting out? Are these punch out fittings?
Each tank will come with at least one permanently mounted patch, it is from the manufacturing process, this is not a fitting and does not unscrew.





I need a clean-out hole for my tank.
We do not offer clean-out ports at this time but there are many options online that allow you to install the needed clean-out port.
You could install a Uniseal fitting into your tank and as long as you have a smooth sided deck mount this could be fitting into the Uniseal.


Dometic Universal Holding Tank Clean-out Kit

Class A Customs does NOT sell this item. You will need to verify if items will fit your application, such as being food safe, we are not aware of this.

Hypro 6" Flat Surface Mounting Male-Threaded Tank Lid & Ring Assm.

Class A Customs does NOT sell this item. You will need to verify if items will fit your application, such as being food safe, we are not aware of this.


8 inch Boat Hatch Cover Deck Plate Hatch,White 8 inch Non Slip Inspection Hatch w/Detachable Cover

Class A Customs does NOT sell this item. You will need to verify if items will fit your application, such as being food safe, we are not aware of this.





All water tanks Class A Customs carries must be gravity fed and vented, they are not pressurized tanks.
Have a certified technician install all parts to prevent product damage and personal injury.

A garden hose (a connection from your faucet indoors, etc. anything that pushes the water) 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. You ca use a Gravity Fill Dish located on the outside of your vehicle to fill the tank, please view the Basic Plumbing Diagram below.
"Venting" the tank lets air move in and out of the tank when in use. Tank must have a large enough opening for air to freely move in and out of tank, if tank is not properly vented tank will explode when filled or implode when emptied. Trying to use a pressurized line "half-way" to prevent damage to the tank will does not work because you can control the amount of water flowing but not the pressure in the line, leaving the tank to fill risks exploding the tank or damaging fittings.






Fresh Water Tank Available Connecting Fittings

Class A Customs Basic Plumbing Kit Part # BPK
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

Water Inlet Items
Fits 1.5" Tank Fittings - Can be used with 1.375" hose

2 (Two) 1.5” Hose Clamps
Can be used with 1.5" Gray Fitting and Fill Dish

Fits 1.5" Gray Fitting and Fill Dish Inlet
1.375" hose can notbe used with spouts on tanks


Vent and Water Pump Items
Fits .5" Tank Fittings - Can be used with .5" Hose for Fill Dish Vents and Water Pumps we sell

4 (Four) .5” Hose Clamp
Can be used with .5" Barb fitting and/or .5" Hose for Fill Dish Vents and Water Pumps we sell

Can be used for Fill Dish Vents and Water Pumps we sell


Drain Items
Fits 1.5" Tank Fittings - Can be used with PVC Pipe to drain

I am going to use a sealed pressurized line to the tank.
This will void any warranty on the tank.
We can easily tell when a tank has exploded due to incorrect usage, you will split the tank or force the fittings out of the tank, again this is not covered under any warranty.



Fill Dish Information

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.






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 / pressurized line 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.


Gizmo Vent Cap VC-M-1.5 - Male Thread - 1.5"

Class A Customs does NOT sell this item. You will need to verify if items will fit your application, such as being food safe, we are not aware of this.


Class A Customs does NOT sell this item. You will need to verify if items will fit your application, such as being food safe, we are not aware of this.






Can I use a water pump with the water tank if I am not using a fill dish?
Using a water pump with the tank pressurizes the water line after the water pump, it does not pressurize the water tank.
Again be sure to have a top fitting on the tank open to let air in when removing water from tank.

You will still need to vent the tank, this can be as easy as placing a fitting with a screen secured over it. Be aware that if you overfill the tank the excess water will exit the vent fitting, placing the vent fitting overflow to an outside location is recommended. Be sure to screen over the vent fitting overflow to prevent anything from entering the tank. Do not over-tighten fittings as damage will occur.

You do NOT use a water pump for the gray or waste water tank.




Gray Tank Available Fittings







Under Sink Gray Tank Set-up Examples
For Gray water tank use you can use any of Class A Customs water tanks, Gray and Waste tanks do not need to be food safe.

To feed directly into the tank you can use a Uniseal Fitting that allows you to place a fitting anywhere in the tank, this is very helpful for concession trailers that want to put the tank under the sink.

Because the Fresh/Gray tanks come with only 1.5" NPT Female fittings and .5" NPT Female fittings built into the tank end user will need to get connecting fittings and adapters that pipe may be installed into.
Depending on the size of the pipe you are using you will need different connecting fittings and adapters, Class A Customs only carries a 1.5" PVC Adapter Fitting - White this may not work for your application, please verify before purchasing.


Additional 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.




Do I need pipe dope or pipe tape to connect the fittings?
It is recommended to use plastic NPT male fittings with the plastic female NPT fittings that are installed in the tank to avoid damaging the threads, metal thread fittings can crush the plastic threads.

Food/Drug Grade Pipe Sealant Pipe Sealant with PTFE EXAMPLE ONLY - We do not sell this item

Very little, if any, pipe thread tape is needed using too much pipe tape will damage the threads. We do not recommend pipe dope as you can not remove the fitting later, if used be sure to use a food safe brand.
Do not over-tighten fittings as damage will occur.


I bought a fitting from my local hardware store and it won't fit.

Be sure you are using NPT fittings and getting the correct sizes. Finding the Correct Pipe Thread Size
You can also print off the items we carry in our Plumbing Category to see if your local hardware store carries them.

Example of Fitting from other suppliers Class A Customs does NOT sell this item. You will need to verify if items will fit your application, such as being food safe, we are not aware of this.

Clean-out Port

Venting Tanks
Suction Line Strainer that Fits Over 1/2" NPT
Only use this with tanks that will overflow outside of your unit, you do not want to overflow inside of unit.






Waste Water Tank Fitting Information


Waste Water Tank Installed Outlet
Black Waste Tanks - 3” ABS Female Pipe - outlet can not be moved -
Gray Waste Tanks - 1.5" ABS Female Pipe - outlet can not be moved - smaller outlet this tank is for dirty water from shower, handwashing, dish-washing

The installed ABS outlet in Class A Customs water tanks uses a specialty adhesive and clamp for extra security.
It is highly recommended to get a tank with the correct ABS outlet size rather than trying to replace it. If you are needing to change out and ABS outlet you can seal it with and ABS/PVC adhesive and clamp, we do not have an adhesive we sell for this application.


Waste Water Tank Inlet & Vent
Class A Customs Waste Water Tanks only come with the ABS outlet installed, the end user will determine where the inlet and vent will need to be placed and install (parts are not included). End user will need to determine size of grommets/Uniseal to be used based on piping and/or toilet flange pipe size.

Grommet (not food safe - waste tank use only) or Uniseal (food safe - fresh/gray/waste use) will secure inlet/vent pipe with no adhesives needed.
Use correct size hole saw bit (listed on item page) in order to drill a hole in the tank and place Grommet or Uniseal in hole, piping is then placed in fitting with no glues or adhesives necessary.


Do Not over-tighten fittings damage will occur.

Dump Valves are not connected directly to the Waste Tank ABS Outlet Fitting, the ABS Outlet Fittings are female fittings and the dump valves are also female fittings, they do not connect.
Use PVC or ABS pipe to connect to the 3" ABS Outlet Fitting installed on the waste tank, the dump valve is then connected to the pipe.

We do not sell glues, Examples Oatey 4-fl oz Green PVC/Abs Transition Cement


You will still need to vent the tank, this can be as easy as placing a fitting with a screen secured over it. Be aware that if you overfill the tank the excess water will exit the vent fitting, placing the vent fitting overflow to an outside location is recommended. Be sure to screen over the vent fitting overflow to prevent anything from entering the tank. Do not over-tighten fittings as damage will occur.

Examples of Items to Vent Tanks - Class A Customs does NOT sell this item. You will need to verify if items will fit your application, such as being food safe, we are not aware of this.



Do you have mounting brackets for your waste water tanks?
Class A Customs Waste Water Holding Tank "J" Style Bracket will only work with tanks that have a lip or mounting place, they will not work on smooth edge tanks with no lips.

Gusseted or Non-Gusseted
Made from steel
Powder coated black
End user will need to determine amount of brackets needed for water tank.

Available in 4 or 6 packs

GUSSETED STYLE (Has side piece welded to offer added strength)







When I get the tank what should I do first?
Sanitize each tank prior to use to remove any debris from the manufacturing process. When tanks are manufactured they do not have the holes for the fittings so holes are drilled and fittings installed, the tanks will have shavings from drilling the holes. We do not flush the tanks due to wanting tanks to be completely new and unused.

Tanks are made in a warehouse so maybe dusty or scuffed, this does not effect the use or safety of the tank, wipe with a damp cloth to remove surface dust or scuffs.




1. Prepare a chlorine solution using one gallon of water and a ¼ cup of household bleach (5% sodium hypochlorite solution)

** DO NOT USE FRESH SCENT OR ANY SCENT ENHANCED BLEACH **

Never mix bleach with ammonia or other cleaners.
Open windows and doors to get fresh air when you use bleach.

With tank empty, pour chlorine solution into tank. Use one gallon of solution for each 15 gallons of tank capacity.
2. Complete filling of tank with fresh water.
3. Allow to stand for three (3) hours
4. Drain and flush with potable fresh water.
Any residual chlorine odor will dissipate naturally.


Using chemical tablets to disinfect water
If you don’t have safe bottled water, water treatment tablets can be used to disinfect water. These tablets are popular among campers and hikers, as well as in other countries. They are available in different sizes and made to treat specific amounts of water.

Follow the manufacturer’s instructions on the label or in the package.
Chlorine dioxide tablets can kill germs, including Cryptosporidium, if you follow the manufacturer’s instructions correctly.

Iodine, tablets with iodine (tetraglycine hydroperiodide), or chlorine tablets kill most germs, but not Cryptosporidium. Water that has been disinfected with iodine is NOT recommended for pregnant women, people with thyroid problems, or those with known hypersensitivity to iodine.
It’s also not recommended for continuous use—don’t use it for more than a few weeks at a time.





Ultraviolet Light (UV Light)
Ultraviolet light (UV light) can be used to kill some germs.
Portable units that deliver a measured dose of UV light help disinfect small amounts of clear water. UV light does not work well on cloudy water because small particles may block germs from the light.
If the water is cloudy, first filter it through a clean cloth, paper towel, or coffee filter OR allow it to settle. Then, draw off the clear water and disinfect it using the UV light.
Always follow the manufacturer’s instructions.


Solar Disinfection
In emergencies, the sun’s rays can improve the quality of water. This method may reduce some germs in the water.
To disinfect water using the sun:
Fill clean and clear plastic bottles with clear water. Solar disinfection is not as effective on cloudy water because small particles may block germs from the light.
If the water is cloudy, first filter it through a clean cloth, paper towel, or coffee filter OR allow it to settle. Then, draw off the clear water and disinfect that water using the sun.
Lay the bottles down on their side and in the sun for 6 hours (if sunny) or 2 days (if cloudy). Laying down the bottles allows the sun’s rays to disinfect the water inside more effectively.
Putting the bottles on a dark surface will also help the sun’s rays disinfect the water more effectively.






Do you use BPA in or on the tanks?
Class A Customs does not carry this chemical nor uses it in the manufacturing process in any way.


Can the tank sit in the sun?
Yes, the tanks are UV-8 Stabilization, however this is not an algae or mold prevention. You will need to keep your tank clean and sanitized.


Will the tank material handle ___________ chemical?
Fresh/Gray Water Tanks & fittings made from DOW NSF International NSF/ANSI Std 61 approved Medium Density Polyethylene (MDPE) Resin and are to be used for Fresh or Gray Water only. We are not aware if the tanks can withstand placing other chemicals onto the tank such as spray foams, paints, adhesives. You would need to verify this information.


Can I pressurize your tanks?
No, all tanks Class A Customs manufactures must be vented (allow air in/out during use), Plumbing Example and Fill Dishes


Can I put boiling water into the tank?
No, boiling water is 212 °F (100 °C) Domestic hot - The temperature used during testing is 60 +/- 2°C (140 +/- 4 °F) and appears in Listings as "D. Hot". This is intended to apply to product applications where the product is used for either cold (ambient temperatures) or hot water up to domestic hot temperatures.


The tank smells like a candle?
Freshly made tanks may smell but it will disappear over time with exposure to air and water.




Someone accidentally put fuel into my water system, can I rinse it and just use it?
Class A Customs does not and can not recommend using a tank for fresh or drinking water after a contaminate such as fuel (gasoline, diesel or any other type of fuel) has been in the tank.

If someone has accidentally placed fuel into your fresh or drinking water supply it is highly recommended that you replace the entire system (water pumps, etc.), we understand this causes a financial strain to you and time down but the risk it simply too high to continue using the product after contamination. Replacing the entire system will ensure there are no possibilities of contamination from any areas that may have been exposed.





Can I use an old black water tank for fresh water if I clean it really good?
No, the health risks from using a previously used waste water tank for fresh or drinking water are extremely high and can not be recommended. Waste water tanks are also made from recycled materials and there is no guarantee if another material (paint / glue/ etc.) has been recycled along with the material, Waste Water Tanks are not for fresh or drinking water use.



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