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OP15 Water System Guide

Stay hydrated and clean on your off-road trips with the OP15’s versatile water system!

Stay hydrated and clean on your off-road trips with the OP15’s versatile water system! This guide covers the 63-gallon potable (two 31-gallon tanks), 17-gallon grey, and 10-gallon black tanks, plus hot water setup and winterizing tips—perfect for your camping needs.

System Overview

  • Potable Water: 63 gallons total from two 31-gallon tanks, ideal for drinking and cooking.
  • Grey Water: 17-gallon tank for wastewater from the sink and shower.
  • Black Water: 10-gallon tank for toilet waste.
  • Pumps: 12V electric pumps supply water to all fixtures, with a Truma Combi system for hot water.

Supplying Water

  • Filling: Use a potable water hose to fill the tanks at the lockable fill points marked with a blue icon.
  • Kitchen and Sink: If your OP15 requires, connect the front tank to the kitchen’s electric tap sink via the quick-connect fitting. 
  • Shower and Toilet: These are permanently hard plumbed in the unit and ready for use at anytime.
  • Hot Water: The Truma Combi heater provides hot water using propane or 12V power—turn on the system and wait 10-15 minutes for heating. 

Pack-Down and Drainage

  • Draining: Turn off the pump switch, open all faucets and the low-point drain valves under the tanks to empty them.
  • Grey and Black Tanks: Use the designated dump valves to release wastewater into an approved disposal site.
  • Winterizing: Add RV antifreeze (2-3 gallons per tank) through the pump, run it through all lines until pink fluid appears, then drain. Flush with fresh water and sanitize before reuse in spring.
  • Pro Tip: Check tank levels regularly to avoid running the pump dry, and clean strainers monthly to maintain flow.

Enjoy clean water on your adventures! Contact 925.215.7315 or info@opuscamper.us for support.