WHAT IS HARD WATER?
All water contains dissolved minerals and nutrients, but some sources of water contain more minerals than others. Water is considered hard when it contains high amounts of calcium-carbonate and magnesium. These minerals – in particular – have a high propensity to adhere to surfaces and form scale on surfaces the water comes into contact with, such as pipes and fixtures. In fact, soap scum and scale buildup on bathroom fixtures are how most people realize they have hard water in their home
DO I LIVE IN A HARD WATER AREA?
85% of American homes have hard water (water with a high mineral content - typically calcium and magnesium). This map shows a general depiction of the hardness of water throughout the United States:

Using Vinegar to Decalcify the Fresh Water Fixtures
- Place 3 gallons of vinegar at the rear winterization/boondock port.
- Connect a short piece of water hose, approximately 2-3 feet long to the port and in the gallon jug of vinegar.
- Turn water heater bypass valve to winterization mode if it is not already set.
- If water pump valves are not already in winterization mode then reconfigure valves accordingly. See diagram under the water pump access panel, in your owner’s manual, on the Oliver forum or online at Oliver University.
- Turn water pump on, open kitchen faucet cold line and let the pump pull the vinegar into the system, run approximately 15-20 seconds and then open the hot water side and allow to run for another 10-15 seconds.
- Open the Bath faucet cold line and run approximately 15-20 seconds, then open the hot side and run for 10-15 seconds.
- Flush the toilet twice.
- Turn off the water pump.
- Flush the system with fresh water.
*In some cases you may have to use more than 3 gallons of vinegar to clean out calcium buildup in the lines and at the fixtures. If this is the case then simply start over with step number one with a new gallon of vinegar and continue until the system has been completely decalcified.
Decalcifying the water heater should be done separate from the fresh water fixtures, such as the faucets and toilet, as vinegar is used in the main fresh water system lines but should not be used in the water heater. You can perform the water heater decalcification prior to performing the vinegar flush or at a completely different time. The Truma will inform you when it is necessary to decalcify and you should follow the guidelines outlined in the Truma manual.
Decalcifying the Suburban Water Heater
- Please ensure that the water heater bypass valve is turned for winterization mode. The valve should be oriented where the valve points to the rear of the camper.
- Depressurize the water heater tank by opening up the pressure relief valve.
- Remove the anode rod using a 1-1/16" socket and drain water, inspect the anode rod and replace if necessary.
- Flush out the water heater with clean fresh water.
- Reinstall anode rod.
Decalcifying the Truma Water Heater
The Truma Water Heater is equipped with an on-board circuit board that will determine when the water heater should be decalcified. The inside switch, if equipped, will flash repeatedly when this process is necessary. Please follow the instructions for decalcifying the Truma water heater in the Truma Water Heater manual.
SUPPORTING ARTICLES
Truma Water Heater Bypass valve pictured below
Suburban Water Heater Bypass Valve pictured below