How to Winterize Your Cirrus 920: Step-by-Step Guide



Proper winterization protects your RV’s plumbing system from freezing temperatures and helps ensure everything is ready to go when camping season returns. Follow these steps to safely winterize your camper.


1. Drain the Plumbing System

This includes:

  • Hot water lines
  • Cold water lines
  • Freshwater tank
  • Gray tank
  • Black tank

Allow everything to drain completely. Once the system is empty, close all drains and valves.


2. Drain the Hot Water Tank


Inside the camper, locate the Alde relief valves under the dinette bench. Open the valves, let it drain completely, and then close it back up.


3. Blow Out the Water Lines (Recommended)


For extra protection, it’s a good idea to blow out the water lines to remove any remaining water trapped in the system.

  1. Connect an air compressor to the city water inlet.
  2. Set the compressor to no more than 40 PSI.
  3. Open one faucet or line at a time.
  4. Allow air to push through the system until no more water sprays out.

While this step isn’t as critical as draining and adding antifreeze, it helps prevent any leftover water from freezing and damaging your pipes.


4. Add RV Antifreeze

  1. Connect a short hose to the Nautilus system.
  2. Set the Nautilus panel to Winterize Mode.
  3. Ensure all faucets, fixtures, and drain valves are closed so the pump can create suction.
  4. Place the other end of the hose into a jug of RV antifreeze.
  5. Turn on the water pump to begin drawing antifreeze into the system.


5. Run Antifreeze Through All Fixtures


Start with the kitchen faucet. Run both the hot and cold sides until pink antifreeze appears.

Repeat this process with:

  • Bathroom sink
  • Shower
  • Exterior shower

This ensures antifreeze fully protects every water line.


6. Protect the Drains and Toilet


Finish the process by protecting the remaining plumbing components. Pour antifreeze down the shower drain, and flush the toilet to bring antifreeze into the bowl. 


Your Camper Is Ready for Winter


Once these steps are complete, your camper is fully winterized and ready for storage until your next adventure.


How to Dewinterize Your Cirrus 920: Step-by-Step Guide



As temperatures warm up and camping season approaches, it’s time to get your Cirrus 920 ready for the road. Dewinterizing your camper involves flushing out the RV antifreeze used during winterization and sanitizing your freshwater system so it’s safe and ready for use.

 

Follow the steps below to properly dewinterize your Cirrus 920.

 

1. Drain Any Remaining Antifreeze

 

This includes:

  • Hot water lines
  • Cold water lines
  • Freshwater tank
  • Gray tank
  • Black tank

Once the system is empty, close all drains and valves.


2. Prepare the System for Sanitizing

 

Once the system is drained, it’s time to sanitize the freshwater system. Attach a hose to the Nautilus panel and set it to Sanitize Mode.

 

3. Mix a Sanitizing Solution

 

Create a bleach solution to disinfect the freshwater system. A stronger bleach solution can be flushed through the system immediately. A weaker solution should sit in the tank longer to properly sanitize.

 

A commonly recommended ratio from RV industry experts such as Go RVing is: ¼ cup of bleach per 15 gallons of water. At this ratio, the sanitizing solution should remain in the system for about 12 hours to effectively sanitize the tank and plumbing.

 

4. Fill the Freshwater Tank with the Sanitizing Solution

 

Place the end of the hose into your sanitizing solution. Turn on the water pump to begin siphoning the solution into the system. 

 

Tip: Put all bleach concentrate into one sanitizing container for easier siphoning.

 

Once the solution begins entering the system, switch the Nautilus panel to Power Fill Mode to speed up filling the freshwater tank.

 

Tip: Monitor the tank level carefully to avoid overfilling.
 

When the tank is full, set the Nautilus panel to Dry Camping Mode.

 

5. Run the Solution Through All Fixtures

 

Run the solution through:

  • Kitchen sink
  • Bathroom sink
  • Interior shower
  • Outdoor shower

 

Be sure to run the solution through both the hot and cold water lines at each fixture.

 

6. Drain the System

 

This includes:

  • Hot water lines
  • Cold water lines
  • Freshwater tank
  • Gray tank
  • Black tank

Inside the camper, you’ll also need to drain the hot water tank:

  • Open the Alde relief valves located under the dinette bench.

 

After everything has completely drained, close all valves and drains.

 

7. Flush the System with Fresh Water

 

Refill the freshwater tank with clean water using Powerfill mode. Then, switch to Dry Camping mode and turn on the water pump.

 

Next, run fresh water through all faucets and fixtures, again using both hot and cold lines.

 

Tip: You may need to repeat the fill-and-flush process several times until any bleach smell is gone.

 

8. Final Drain

 

Drain the system one last time and turn off the water pump.

 

Your Camper Is Ready for the Camping Season

With your freshwater system clean and operational, you can focus on the fun part, planning your next adventure.


Guide to the Nautilus P3 System

This article and video applies to any nuCamp model equipped with the Nautilus P3.


The Nautilus P3 system is used in the 2025 TAB 320, TAB 360, TAB 400, Cirrus 620, Cirrus 820, and Cirrus 920 models to streamline water management by centralizing essential functions. Below is an overview of its components, functions, and modes.




Step 1: Understanding the Nautilus Panel Components

The front panel of the Nautilus system includes the following key components:

  • City Water Hookup – Connects to city water for direct supply.
  • Black Tank Flush Hookup – Used to clean out the black tank by flushing it with fresh water.
  • Coax Connection for Interior TV – Provides a TV connection inside the camper.
  • Water Pump Switch – Turns on the water pump (identical to the interior pump switch).
  • External Shower – Allows access to hot and cold water outside the camper.
  • Mode Selection Knobs – Adjusts the system’s settings for different functions.
  • Instruction Key Sticker – Provides visual guidance on knob positions for each mode.

Step 2: Nautilus Panel Modes

1. Dry Camping Mode

  • Allows you to pump water from the freshwater tank to your fixtures.
  • Ensure the pump is turned on, either at the Nautilus panel or inside the camper.

2. Power Fill Mode

  • Used to fill the freshwater tank using a garden hose.
  • Connect the hose to the City Water Hookup and allow it to fill the tank.

3. City Water Mode

  • Directly supplies water from a city water connection to your fixtures, bypassing the freshwater tank.
  • No need to use the pump in this mode.

4. Sanitize Mode

  • Used when de-winterizing or sanitizing the system.
  • Connect a bucket or container to the City Water Hookup and siphon liquid into the fresh tank.

5. Winterize Mode

  • Used only during winterization to run RV antifreeze through the system.

Step 3: Using the Black Tank Flush

  • Connect the city water hose to the Black Tank Flush Hookup.
  • This allows fresh water to be forced through the black tank, helping flush out residual waste.

Important Notes:

  • Always use an inline water pressure regulator when connecting to city water (included in your welcome pack).
  • Follow the instructional sticker on the Nautilus panel for proper knob positioning.


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How to Flush the Black Tank


The black tank flush is a useful feature that helps you maintain your RV’s black tank. Whether you're prepping for storage, maintaining accurate tank sensor readings, or simply keeping your tank clean, using the black tank flush can make a big difference in the longevity and functionality of your system.


When Should You Use the Black Tank Flush?

You might consider using the black tank flush in the following situations:

  • Tank sensors are reading inaccurately: If your monitor panel shows incorrect readings, residue buildup could be to blame.

  • Before winter storage: Flushing the tank before storing your RV can prevent unpleasant odors and buildup.

  • Regular maintenance: Periodic flushing helps reduce the buildup of gunk and keeps the tank in good working condition.

How to Use the Black Tank Flush

Follow these steps to safely and effectively use the black tank flush:

  1. Hook up your sewer hose
    Always ensure your sewer hose is properly connected to a dump station or appropriate waste outlet.

  2. Locate the black tank flush inlet
    This is usually labeled and located on the exterior of your RV.

  3. Connect a garden hose
    Attach one end of a garden hose to the black tank flush inlet.

  4. Connect the other end to a water source
    Use a hose that is separate from your drinking water hose, and always connect through an inline pressure regulator to avoid over-pressurizing the system.

  5. Monitor tank levels
    It’s important not to overfill the tank. You can monitor your tank levels in one of two ways:

    • Use your tank monitor panel to keep an eye on the black tank fill level.

    • Open the toilet valve and visually inspect the tank level.

  6. Stop the flush when nearly full
    Once the tank is nearly full, shut off the water and disconnect the hose.

  7. Empty the black tank
    Drain the contents of the black tank into the sewer connection.

Need Help?

If you have any questions or need assistance, feel free to reach out to our tech team at Tech@nucamprv.com.