Got one of these?  It’s a suburban lpg / 12v gas water heater and by far the most popular one installed in most motorhomes and caravans today.

Keeping it in great shape by maintaining a few bits n bobs regularly will ensure that you get a longer life out of it, with many years of on the road hot water in your motorhome or caravan.

This post explains the ins and outs of the tank itself and what you can do to keep it maintained yourself.

The tank in this water heater is protected by a magnesium or aluminum anode to prolong the life of the tank by absorbing the corrosive action of hot water. Under normal use, the anode rod will deteriorate and because of this, we recommend it be replaced yearly.

Water with high levels of iron and/or sulfate will increase the rate of deterioration; therefore, more frequent replacement may be required. If anode rod is mostly eaten away, replace it with a new one.  To prevent a water leak when replacing the anode rod, a pipe thread sealant approved for potable water (such as Teflon Tape) must be applied to the threads of the anode rod. Proper application of a thread sealant will not interfere with the anode’s tank protection.

Operating the water heater without proper anode protection will decrease tank life and will void your warranty on the tank. NOTE: Tank is drained by removing anode rod. To extend anode life, drain water from tank whenever RV is not being used.

Avoid any extended time of non use with water in tank.

Turn Off Water Heater

  1. Turn water heater switch to off
    2. Turn off electrical power to the appliance
    3. Turn off gas supply (gas cylinder/bottle)

NOTE: For safety reasons, turn the water heater off the night before to let the hot water in the storage tank ‘cool’ first to avoid any chance of scalding from hot water before proceeding with the following steps –

Replacing the Sacrificial Anode

  1. 4. Wrap top of new anode in a clockwise direction thread with sealant tape. Don’t put the sealant tape on too thick or you will have difficulty tightening the anode. Have the wrench and socket close at hand.
  2. Turn off the water pump inside the RV/ turn off town water – then turn the water tap in sink to ‘hot’ water and let run out as this depressurises the hot water tank.
  3. Attach the socket wrench to the anode top and unscrew (counter clockwise) and remove the anode.  Water (may include some coloured gunk – you may want to place a bucket underneath to catch this) will pour out so stand back and be careful to avoid scalding. Let the water heater tank drain out.  Then, using another hose connected to mains water, inset it into the tank to flush out any sediments. Shut off the ‘hot’ water tap inside the RV and turn the water pump back on waiting until the water flowing outside is clear.
  4. As soon as water is clear, turn off the water pump, and then insert the new anode and tighten (clockwise). The anode may not tighten all the way to end of thread. Do not over-tighten.
  5. Turn on one ‘hot’ water tap and the water pump in RV. Be patient and wait as the water is re-filling the hot water storage tank.  Once it is full, water will come through the hot water tap. Turn the tap off.
  6. “Bleed” the air out of the HWS storage tank by lifting the small valve handle outside on the appliance until the water flows out continuously. Check the unit for any water leaks.
  7. Unit is then ready to turn on power/gas for heating.
  8. Clean up and then order another anode as a spare.