Trailer Owner’s Manual

6 Preparing for a Trip

6.1 Loading Water

Depending on how the trailer is loaded, the trailer might tow better either with a full or empty tank of water. See Section 6.5 (Packing the Trailer and Tow Vehicle) for details.

Filling the Fresh Water Tank

Use a hose to load water through the fresh water tank fill. While filling the water, air escapes through a small vent hole above the fill opening. Stop filling when the water begins to overflow the fill inlet, and replace the cap. See Figure 5a.

Water may also be supplied to the trailer via the “city water” connection. (Figure 5b) This water supply does not go to the fresh water tank, but it does go to the hot water heater and the faucets.

Figure 5: Water Connections



(a) Fresh Water Tank Fill



(b) City Water Connection

Releasing Air from the Hot Water Heater

If a hot water heater is installed, fill the fresh water tank, then turn on the water pump to move water from the fresh water tank into the hot water heater. After some time, the water pump will stop, indicating that the hot water tank also has water. If the hot water heater is cool, then air which is trapped in the top of the hot water tank may be released by temporarily opening the hot water pressure-release valve. This can cause the water pump to resume pumping to add additional water to replace the air which was released. Only do this if the water in the hot water heater is cool. Figure 6a shows the pressure-release valve closed, which is the normal position. Figure 6b shows the valve opened to temporarily let air out.

Figure 6: Water Heater Pressure-Release Valve



(a) Closed



(b) Open

Close the pressure-release valve once water starts to come out. Turn off the water pump once it has stopped filling the hot water tank.

Releasing Air from the Water Lines

Air may be trapped in the water lines after water has been added to the system. Remove this air by opening each faucet while the water pump is turned on or while the trailer is connected to a shore water supply. Close the faucet once the air has been removed from each of the hot and cold sides of the water system.

6.2 Connecting the Batteries

The batteries (one or two) are connected to the trailer with two electrical cables. The colors of these cables follow either of two standards. See Figure 7.

If the cables are red and black, then they are following the automotive standard of red/positive and black/ground. The red cable goes to the (+) battery terminal, and the black cable connects to the (–) terminal.

If the cables are white and black, then they are following the housing standard of black/hot and white/neutral. The black cable goes to the (+) battery terminal, and the white cable goes to the (–) terminal.

There will also be an additional cable which goes to the frame of the trailer, and this cable must go to the (–) terminal of the battery.

In the event that the battery is miss-wired, a fuse near the battery’s (+) terminal or else fuses inside the trailer’s converter panel will be blown and the 12 V dc system will be inoperable until the wiring is corrected and the fuses are replaced.

Figure 7: Battery Wiring — Two Color Standards


The trailer frame has brackets which are designed to hold one or two vented plastic battery cases, commonly available at automotive or rv supply stores. Each case must be attached to the frame brackets to prevent it from sliding, and each case with its enclosed battery must be strapped down to the frame brackets. For added security, the strap may be replaced by a locking clamp, available from mail-order sources.

The battery cases have gaps near the top where the wires are routed to go to the battery terminals. Be sure that the wires go through these gaps and are not pinched by the top of the case when the case is closed.

6.3 Connecting the LP Tanks

For a diagram of the lp tank connections, see Figure 15 (LP Gas System).

Place each lp (“Liquid Petroleum” or “propane”) tank upright on the bracket, turned such that each hose can connect directly to the tank nozzle. Clamp each tank down from above. Check this clamp on occasion for tightness.

Connect each hose to each lp tank using the green knob with moderate hand tightness. Do not over tighten.

Keep each lp tank’s valve in the closed position until the hose is connected and the lp tank will actually be used for heating or cooking.

If possible, use the 120 V ac power mode for the refrigerator during preheating and packing, and during travel use the 12 V dc power mode instead of the lp gas mode, allowing the lp tank valves to remain closed until you have arrived at camp.

6.4 Loading the Refrigerator

The refrigerator cools slowly, so it should be pre-cooled for a day before loading it with food.

Be sure to close and latch the refrigerator door, then turn on the refrigerator with either lp propane or 120 V ac electric “shore” power. Do not use 12 V dc battery power since this will drain the trailer battery unless the trailer is plugged into a 120 V ac power source. The 12 V dc fridge option is not recommended even if shore power is available, since the fridge cools more efficiently with either lp propane or 120 V ac power.

If possible, pre-cool the food before loading it into the refrigerator.

Load food loosely in the refrigerator, allowing air to circulate inside the fridge. An overly-full refrigerator will not cool evenly.

Once loaded, be sure that the door is closed and secured with its latch. With some models, it might be possible to adjust the latch for tightness.

6.5 Packing the Trailer and Tow Vehicle

See Figure 21 (Extra Forces On The Vehicle While Towing) for an illustration of the below discussion.

Where the cargo is positioned in the tow vehicle or trailer can be important.

When the trailer is connected to the tow vehicle, it presses down on the back end of the tow vehicle. Too much weight on the back of the tow vehicle can cause problems with steering and stability, and too little weight can cause the trailer to sway side to side as it is being pulled down the road.

It is recommended that the trailer be packed such that 10% to 15% of its own weight is on the trailer hitch. This can be accomplished by placing heavier cargo in front of the trailer’s axle. Avoid placing most of the cargo in the far back of the trailer, which can result in side to side swaying of the trailer as you drive down the road.

If the trailer is pressing down on the hitch so much that the front of the tow vehicle is pointing noticeably upwards, then cargo in the trailer may be moved somewhat further back to help take weight off of the hitch. Another possibility is to move cargo in the tow vehicle forward away from the hitch.

Water in the fresh water and hot water tanks count as cargo weight. These tanks are behind the trailer’s axle, so water added to the tanks means less weight on the trailer hitch and a greater likelihood of trailer sway.