09 2026 GH Series Plumbing and Bath Features

Kitchen Sink

The Tiffin GH Series kitchen is a leap into bold innovation, where the benefits of a stainless-steel single bowl sink (Figure 9-1) with a built-in sprayer go beyond aesthetics, transforming your space into a fortress of style and utility.

Stainless steel is known for its durability, resistance to rust, and ease of cleaning, making it a reliable choice for busy kitchens. The single bowl design offers plenty of space for washing large pots, pans, and baking trays, which can be challenging in other sinks. The built-in sprayer adds extra convenience, allowing you to rinse dishes effortlessly and clean hard-to-reach areas. With its sleek design and functional features, this type of sink enhances both the practicality and style of your kitchen setup, making everyday tasks more efficient and enjoyable.

Keeping the single-bowl sink and built-in sprayer faucet clean is simple, requiring only regular maintenance and gentle cleaning to preserve its functionality and appearance. Begin by rinsing the sink and faucet with warm water to remove debris. Use a mild dish soap and a soft sponge or cloth to gently scrub the surfaces, steering clear of abrasive materials that could scratch the stainless steel. For stubborn stains or mineral buildup, applying a vinegarwater solution can be highly effective. Allow it to sit for a few minutes before wiping clean. Dry the sink and faucet with a soft towel to prevent water spots and finish with a stainless-steel cleaner for a polished look. Regular maintenance like this keeps the sink and faucet in excellent condition.

Your unit is equipped with a galley macerator pump, designed to efficiently manage waste disposal. To activate the pump, locate the switch on the galley base cabinet (Figure 9-2). Simply push and hold the switch to run the pump, allowing for smooth operation. When you're ready to stop the pump, release the switch, and the system will immediately halt its function. This straightforward mechanism ensures seamless usability, making waste management in the galley both convenient and efficient.

 

Shower

The TIFFIN GH Series is equipped with a well-designed wet bath that maximizes space and functionality. It features a shower that also accommodates the toilet, complemented by a removable, magnetic shower curtain and a detachable shelf for added convenience. Additionally, a built-in storage compartment provides designated space for soap, shampoo, and other toiletries, ensuring everything stays organized and easily accessible. A built-in toilet paper holder further enhances convenience by keeping necessities within reach (Figure 9-3).

To open the shower doors, rotate the latches (Figure 9 -4) located at the top to disengage the locking mechanism (Figure 9 – 5). This design ensures secure closure while providing effortless access when needed. For safety and stability, always verify that the shower doors are securely closed before the van is in transit. Properly securing the doors prevents unnecessary movement and potential damage, ensuring a reliable and wellmaintained interior during travel.

      

 

Shower Operation

Tiffin GH Series features a ShowerMiser (Figure 9-6), an innovative and highly efficient system engineered to enhance water conservation. Its main purpose is to conserve water by redirecting cold water that would typically go down the drain while you're waiting for the hot water to arrive. Here's how it works:

Recirculating Cold Water: When you turn on the shower, the cold water is rerouted back into the freshwater tank instead of being wasted in the gray water tank.

1. Indicator System: The ShowerMiser has a colorchanging indicator (Figure 9-7) that lets you know when the water is hot and ready for use.

2. Simple Operation: To operate the system, simply adjust the lever (Figure 9-8) ensuring a seamless and user-friendly experience.

This system is especially useful for dry camping, as it helps extend the capacity of both your fresh and gray water tanks.

      

 

 

Water Pump

The water pump is used to pressurize the fresh water system when the unit is not connected to city water.

How to Start the Water Pump

1. Fill the Freshwater Tank

•  Completely or partially fill the freshwater tank to ensure an adequate supply.

2. Open Faucets

•  Turn on both the kitchen and bathroom faucets to allow air to escape from the system.

3. Power On the Water Pump

•  Switch the water pump to the “ON” position and let it run until the water fills the lines.

4. Close Faucets Gradually

•  Once a steady stream of water flows, close each faucet, starting with the cold-water faucet first.
•  Leave the hot water faucets open until they also deliver a steady stream, then close them.

5. Pump Operation Check

 

 

Important Maintenance Notes

•  Avoid Dry Running: Never let the pump operate for extended periods without water in the supply tank, as this can cause damage to components or blown fuses.
•  Drain System When Not in Use: If the van will be unused for an extended time, drain the entire freshwater system to prevent buildup or damage.

Here are some troubleshooting tips for water pump on the Tiffin GH1 van:

Common Issues & Fixes

1. Pump Won’t Start

•  Check if the pump is receiving 12V power.
•  Inspect loose wires or a blown fuse.
•  Ensure the switch is turned on.

2. Pump Runs But No Water Flow

•  Verify that the freshwater tank is full.
•  Check for clogged filters or blocked hoses.
•  Inspect for air leaks in the system.

3. Pump Won’t Shut Off

•  Look for leaks in the plumbing system.
•  Ensure the pressure switch is functioning properly.
•  Check for air trapped in the lines.

4. Low Water Pressure

•  Clean or replace clogged faucet aerators.
•  Inspect for kinked hoses or blockages.
•  Check if the pump diaphragm is worn out.

5. Pump Cycles On & Off Frequently

•  Look for small leaks in the system.
•  Ensure the pressure tank is working correctly.
•  Check for faulty check valves.

 

Sewer Bay

The Tiffin GH Series is equipped with the state-of-the-art Nautilus P3 Sewer Board (Figure 9-9); designed to simplify water management with efficiency and reliability. This innovative system allows seamless control over freshwater tank filling, city water connection, sanitation, and winterization, ensuring a hassle-free experience for RV owners. Its intuitive interface clearly marked handles, and user-friendly operation make adjusting water flow effortless. Additionally, the Nautilus P3 is engineered for easy maintenance, featuring smooth surfaces and accessible components that facilitate quick cleaning. Whether preparing for travel or winterizing the system, the Tiffin GH Series integration of the Nautilus P3 Sewer Board enhances convenience and reliability on the road.

Sewer Bay System Overview

The operational guidelines for the Nautilus P3 valve system are as follows:

1. White Handle:

•  Function: Receives water from the inlet located on the front panel.
•  Sideways Position: Directs water to the pump inlet.
•  Downward Position: Channels water into the blue-handled diverter.

2. Blue Handle:

•  Function: Receives water from the white-handled valve, connected to the inlet on the front panel.
•  Sideways Position: Facilitates water flow to the cold-water fixtures.
•  Downward Position: Allows water to flow to or from the freshwater tank.

3. Green Handle:

•  Function: Serves as an on/off valve controlling water flow from the freshwater tank to the pump.
•  Sideways Position: Water will not flow through the valve.
•  Up Position: Water will go to or come from freshwater tank.

4. Red Handle:

•  Function: Receives water from the cold-water supply line.
•  Sideways Position: Routes water directly to the hot-water fixtures, bypassing the hot water heater.

5. Red Handle:

•  Function: Receives water from the cold-water supply line.
•  Sideways Position: Routes water directly to the hot-water fixtures, bypassing the hot water heater.

 

 

 

 

 

City Water Connections

To establish a reliable connection to the city water supply, begin by attaching one end of the hose to the designated city water inlet (Figure 9-10), located on the sewer board. This standard connection ensures a direct and consistent supply of water to your unit. Alternatively, for enhanced security and convenience, you may opt to connect the city water hose to the auxiliary port positioned on the passenger side of the unit, located behind the rear tire (Figure 9-11). This secondary connection option allows you to shut and lock the rear doors of the van while maintaining a full-time link to the city water supply. Using this setup provides added protection against potential external interference while preserving accessibility to running water. Regardless of which method you choose, always ensure that the hose used is specifically manufactured and labeled for potable water service to maintain optimal water quality and prevent any alteration to the taste of the water. Proper connection and routine inspection of the fittings and hoses will help sustain an uninterrupted and dependable flow of water for extended use.

  

Turn the city water supply “on” for a few seconds to clear the line. Once the hose has been flushed, turn the supply “off.” Connect the other end of the hose to the inlet valve on the sewer board or outside inlet; turn the blue handle valve on the sewer board to the city water fixtures turn the red handle valve on the sewer board to normal. (Note: As the water goes through the inlet and then passes through the filter ensuring that all water exiting the faucets and showers have been filtered). Once the city water fill valve is opened, water is supplied to the freshwater system including the water heater, faucets, and toilet. Turn “on” the water supply and open all the faucets to clear any trapped air within the plumbing lines within the motor home.

Once any air pockets have purged from the water lines and water flows freely, close all the faucets. The city water supply is pressurized; therefore, the water pump is not needed when the water system of the vehicle is connected to the city water system.

The valves should never be turned while there is pressure on the lines.

The freshwater tank is normally filled from the city water inlet on the sewer board. The red and blue handle valves located on the sewer board determine whether the city water is going through the water system or into the freshwater tank. To fill the freshwater tank, turn the blue handle valve to city fill tank, turn the red handle valve to normal. Since there is no automatic shut-off when filling the freshwater tank, check the level from the monitor panel while filling the freshwater tank on the motorhome. (NOTE: As your freshwater tank fills the water passes through the filter ensuring that the water in the freshwater tank has been filtered before use).

To ensure proper maintenance of your Tiffin Van freshwater system, begin by turning the chrome valve to the vertical position, allowing water to drain from the lines and tank. Once the drainage process is complete, return the valves to the horizontal position to securely close them. When filling the freshwater tank or utilizing city water, always verify that the valves remain in the closed position to prevent unintended water loss. Additionally, if the Tiffin Van will be unused for an extended period, it is essential to drain all water from the freshwater system to prevent damage and maintain optimal sanitation.

The freshwater drain board is positioned on the passenger side beneath the galley base. To access the valves, open the sliding passenger door. Adhering to proper valve management and drainage procedures will ensure the efficiency and longevity of your Tiffin Van water system, promoting reliable operation throughout your travels.

 

Run Hot and Cold Fixtures from Fresh Water Tank

After filling the freshwater, you are ready to run the water system from the freshwater tank supply.

1. Turn “on” water pump.

2. On the sewer board turn the blue handle valve to the normal position and turn the red handle valve to the normal position.

Sanitizing Hot and Cold Fixtures and Fresh Water Tank

To assure complete disinfecting of the freshwater system, it is recommended that the following procedures be performed on a new system, on one that has not been used for a length of time, or one that may have become contaminated. This procedure is also recommended before long periods of storage, such as during the winter months:

1. Drain the freshwater tank by opening the drain valve. All the faucets should be in the closed or “off” position.

2. Prepare a chlorine solution using one gallon of water and one-half cup of chlorine bleach (5% sodium-hypochlorite solution). Prepare enough of the chlorine solution to administer one gallon of solution for every 15 gallons of tank capacity. Concentrations greater than 50 ppm may damage the water lines and/or the tank.

3. Once the freshwater tank is empty, close the drain valves in the water tank.

4. Pour the solution into the gravity fill which is located on the rear of this coach.

5. Turn “on” the water pump. On the sewer board turn the blue handle valve to “normal” position and turn the red handle valve to “normal” position.

6. Open each faucet, in turning “on” both the hot and cold faucets and flushing the toilet until all the air has been purged from the pipes and the water runs freely. The entire system will then be filled with the sanitizing solution.

7. Allow the 50-ppm disinfecting solution to stand in the system at least four hours.

8. Drain the system and flush it with freshwater. The water system needs to be flushed with water repeatedly, if necessary, until there is no chlorine taste or smell left in the system. To remove any excessive chlorine taste or odor that might remain, prepare a solution of one quart of vinegar to five gallons of water. “Rock” the tank containing the solution; by moving the vehicle forward and backward several times to clean the tank; then drain that tank and refill with clean water.

 

Sanitizing Hot and Cold Fixtures Only (Not Fresh Water Tank)

1. All faucets should be in the closed or “off” position.
2. Prepare a chlorine solution using one gallon of water and one-half cup of chlorine bleach (5% sodium-hypochlorite solution). Concentrations greater than 50 ppm may damage the water lines.
3. Connect one end of the vinyl hose to the inlet valve on the sewer board; place the other end of the hose into the solution that has been prepared.
4. Turn “on” the water pump. On the sewer board turn the blue handle valve sanitize/winterize and turn the red handle valve to bypass.
5. Open each faucet, in turning “on” both the hot and cold faucets and flushing the toilet until all of the air has been purged from the pipes and the water runs freely. The entire water lines will then be filled with the sanitizing solution.
6. When the sanitizing process is completed, turn the water pump “off”.
7. Allow the 50 ppm disinfecting solution to stand in the system at least four hours.
8. Drain the system and flush it with freshwater. The water lines will need to be flushed with water repeatedly, if necessary, until there is no chlorine taste or smell left in the system. To remove any excessive chlorine taste or odor that might remain, prepare a solution on one quart of vinegar to five gallons of water. Repeat steps four, five and six to run the solution through the water lines. Drain the system and flush with freshwater.

Toilet

The toilet in your Tiffin GH Series is designed for ease of use, efficient waste management, and longterm reliability. Proper operation and regular maintenance ensure maximum sanitation, functionality, and longevity.

To adjust the orientation of the toilet bowl, begin by closing the cover to prevent accidental movement of internal components. Using both hands, firmly grip the toilet bowl and rotate it to the desired position, keeping in mind that it has a maximum rotation of 90 degrees clockwise (Figure 9-13). This adjustability allows users to optimize the positioning of the toilet within the available space for enhanced comfort and convenience.

To ensure an efficient flush, always verify that the blade (Figure 9-14) is fully open before proceeding. Press and hold the flush button (Figure 9-15) for several seconds to initiate the flushing process. If needed, pulsating the flush by pressing the button multiple times in quick succession can enhance the effectiveness of the flush and promote thorough waste removal.

Your toilet is equipped with a level indication system for the wasteholding tank. When the slide transitions from green to red, it signals that the waste-holding tank is full and requires emptying to maintain optimal performance and hygiene. Regularly monitoring this indicator will help prevent overfilling and ensure smooth operation.

This toilet system is highly versatile, operating effectively with water from either the freshwater tank (with the water pump turned “on”) or directly from the city water supply when connected. This dual-source functionality ensures continuous availability of flushing water in different scenarios, providing flexibility for various conditions and user preferences.

Before each use, it is essential to add water to the bottom of the toilet bowl to ensure efficient waste movement and flushing. Proper pre-use preparation prevents waste from sticking to the bowl surface and improves overall sanitation. The toilet flushes waste directly into the black water holding tank, which serves as a containment system for wastewater until it is properly emptied at an appropriate disposal station. Regular monitoring of the black-water tank levels is advised to prevent overfilling, which may lead to system inefficiencies or unpleasant odors.

To maintain the highest standards of hygiene and operational efficiency, the toilet should be cleaned regularly. Routine cleaning helps prevent buildup of waste residue, bacteria, and odors, ensuring a fresh and sanitary environment. It is recommended to use a mild bathroom cleaner specifically formulated for toilet surfaces to avoid damage to the materials. Avoid harsh chemicals or abrasive scrubbing tools, as they may degrade the finish or weaken components over time.

By following these operational and maintenance guidelines, users can maximize the performance, hygiene, and lifespan of the toilet system, ensuring a comfortable and sanitary experience. Regular inspections and proper use will contribute to long-term reliability and convenience.

Never add toilet additives directly via the valve blade or via the toilet bowl as this could damage the lip seal of the waste-holding tank. Only fill the waste-holding tank via the pour out spout.

Never use force if you cannot get the waste-holding tank back into place easily. If blockage occurs, always check if the blade handle is in the closed position.

 

Wastewater Disposal

Your toilet is equipped with a streamlined waste-holding tank level indicator (Figure 9-16), designed for efficient monitoring—when the slide transitions from green to red, it signals that the tank is full and requires emptying. To ensure proper maintenance, begin by removing the waste-holding tank from the outside toilet tank door (Figure 9-17) and fully extend the pull handle before transporting it to an authorized waste disposal facility. Once positioned, place the tank upright, rotate the pour-out spout upward, and remove the cap. While keeping the pour-out spout angled downward, press and hold the vent button to facilitate a controlled and thorough emptying process. After disposal, introduce approximately five liters of water into the tank, securely replace the cap, and gently shake the unit to ensure internal cleanliness before emptying it again. Additionally, detach the float by rotating it clockwise and rinse it thoroughly with tap water to maintain optimal function. Conclude the process by retracting the pull handle until it locks securely, reinserting the waste-holding tank into the toilet, and closing the service door. If further use of the toilet is required, properly prepare the waste-holding tank for continued operation.

   

 

Sewer Connection and Camping

The Tiffin GH Series is designed with convenience and sanitation in mind. The gate valve and grey water dump connection (Figure 9-18) are strategically placed on the driver’s side, just in front of the rear tire, making it easy to access and manage waste disposal. Additionally, Tiffin provides a dedicated holding compartment for the sewer hose (Figure 9-19) at the rear of the van, ensuring a clean and organized storage solution. This feature helps maintain hygiene by keeping the sewer hose separate from other equipment, preventing contamination and making waste disposal more efficient.

   

While using the van, it is crucial to always maintain the greywater holding-tank gate valve is in the closed position, except when actively dumping the contents. This practice helps ensure that enough liquid remains inside the tank, which plays a vital role in facilitating an effective and efficient draining process. Keeping the valve closed allows waste liquids to accumulate, preventing premature leakage and ensuring that the waste materials have ample fluid to mix with.

When the time comes to empty the holding tank, having a generous amount of liquid within it promotes a smoother outflow through both the gate and drain valves. The presence of an adequate liquid volume encourages a swirling motion inside the tank, which is beneficial for loosening and carrying away accumulated solid waste. This swirling action helps break down waste deposits that might otherwise stick to the interior surfaces of the tank, minimizing the chances of blockages and making the overall dumping process more thorough and effective.

Additionally, maintaining a closed valve when not dumping reduces the risk of unwanted odors escaping from the tank and helps prevent clogs by allowing solid waste to mix with the liquid over time. It also extends the longevity of the system by ensuring proper waste disposal and minimizing residue buildup inside the tank. By following this method consistently, van users can maintain a more sanitary and hassle-free waste management system, avoiding common issues associated with improper dumping practices.

Using the gate valve and grey water dump on the Tiffin GH Series is a straightforward process, but it’s important to follow the correct steps to maintain sanitation and efficiency. Here’s how to do it:

1. Prepare the Dumping Area – Park your van at an approved dump station or designated wastewater disposal area. Make sure you have proper drainage access.

2. Retrieve the Sewer Hose – Open the holding compartment for the sewer hose located at the rear of the van and connect the hose to the dump station.

3. Attach the Hose to the Dump Connection – Securely connect the other end of the sewer hose to the grey water dump connection on the driver’s side, in front of the rear tire.

4. Open the Gate Valve – Pull the gate valve handle to release the grey water waste into the sewer hose. Always ensure the valve is fully opened to allow complete drainage.

5. Monitor the Flow – Keep an eye on the draining process to make sure all waste is emptied efficiently.

6. Close the Valve – Once the tank is empty, close the gate valve completely to prevent any residual leakage and allow liquid to accumulate for the next use.

7. Flush & Clean – If possible, flush the tank with clean water to remove remaining residue, then detach the sewer hose.

8. Store the Hose Safely – Disconnect the hose, rinse it, and return it to the holding compartment at the rear of the van.

Following these steps ensures a smooth and hygienic dumping process while maintaining the longevity of your system.