🧊 Modtub Quick Start Guide

Welcome to the Modtub family! Follow these simple steps to get your cold plunge set up and running safely and effectively.

✅ 1. Fill Your Modtub

• After setting up your tub according to the assembly instructions, attach the included hose filter to your garden hose.
  
  

• Before filling, run water through the hose for 10 seconds to flush out excess charcoal dust from the filter.
  
  

• Fill the tub to your desired level; for most people this is just above the return jet
  
  

💡 Pro Tip: Make sure your Modtub is on a level surface and has at least 12 inches of clearance behind it for proper airflow and servicing.

⚡ 2. Power Up Safely

• Do not plug in the power cord until the tub is completely filled.
  
  

• Once filled, plug in the unit.
  
  

💡 Pro Tip: Make sure the green switch on the side of the chiller is powered on after plugging in.

💧 3. Set the Pump Flow

• Locate the pump control dial and turn it to your desired setting.
  
  

• We recommend starting at 75%, but never below 50%.
  
  

• Verify water flow by placing your hand in front of the return jet inside the tub.
  
  

👀 4. Check for Leaks

• Once water is circulating, observe the tub for 10 minutes.
  
  

• Ensure there are no leaks and that all hose and plumbing connections are tight.
  
  

💡 Note: Condensation is normal when humid air contacts cold surfaces and may appear like small drips on the outside of the tub or hoses. Leaks typically involve pooling or dripping from a connection point — be sure to distinguish between the two.

🧪 5. Add Water Sanitation

• After confirming water flow and tight connections, add any water treatment products you plan to use (e.g., chlorine, bromine, hydrogen peroxide).
  
  

❄️ 6. Set Your Desired Temperature

• Press the “SET” button on your chiller.
  
  

• Use the ▲ / ▼ arrows to select your preferred temperature.
  
  

• Press “SET” again to confirm and lock in your selection.
  
  

The system allows a minimum set temperature of 39°F.

🌡️ 7. Understand the Temperature Deadband

• Once your water reaches the set temperature, the unit will enter standby mode.
  
  

• It will restart when the temperature rises 2°F above the set point.
  
  

  • Example: If set to 39°F, the system will maintain between 39–41°F — this range is called the “temperature deadband.”
    
    

🕒 8. Cooling Time Expectations

• Your water will cool down at an average rate of 2–5°F per hour, depending on ambient temperature and starting water temp.
  
  

🔄 9. Continuous Operation

• Your Modtub is designed to run 24/7 for consistent performance.