Grand Design Momentum, Owner'S Manual

Page: 200 / 220

198
Basic Troubleshooting
Water Heater, Continued
5. If you decide to use air pressure (55 PSI max.), it may be
applied either through the inlet or outlet on the rear of the
tank. It may also be applied through the relief valve port.
◦
First remove the relief valve. You may then insert your
air pressure through the relief valve support flange.
◦
With the drain valve open, the air pressure will force
the remaining water out of the tank.
◦
If air pressure is unavailable, you may flush the tank
with fresh water. Water should be pumped into the tank
with the assistance of the on board water pump or with
the assistance of external water pressure.
◦
External pressure may be pumped into the unit either
through the inlet or outlet found on the rear of the
water tank, or using the relief valve inlet located on the
front of the unit.
6. Continue this flushing process for approximately five (5)
minutes allowing ample time for the fresh water to agitate
the stagnant water on the bottom of the tank and force
the deposits through the drain opening.
7. Upon completion of the steps above, close the drain plug
as well as the relief valve. Refill with fresh water, circulate
and rinse.
If you use your vehicle frequently or for long periods of time,
flushing the water heater several times a year will prolong the
life of the water heater storage tank.