refrigerator power

I'm planning a two week trip in the spring and want to know about leaving the refridgerator hooked up to the battery while traveling. My question is when I stop to sight see is it going to drain the battery? What are my options?

[Wavery]

Originally Posted by travelinklunts

I'm planning a two week trip in the spring and want to know about leaving the refridgerator hooked up to the battery while traveling. My question is when I stop to sight see is it going to drain the battery? What are my options?

Make sure that you have a charge line from your TV to the trailer first.

It is not a good idea to leave the fridge on 12V when you are stopped. It can run the battery down in a few hours or less. Whatever the amount of time, it isn't worth coming back and finding a dead battery.

We always run our fridge on propane while traveling. I just make sure that the fridge cooling fan is turned on. We've never had an issue.

The other option, if you want to run on 12V (which is less efficient BTW), is to disconnect your trailer harness while you are off site seeing.

If I stop for gas, I leave it running on 12 volts.

If I stop for dinner or longer, then I unplug the TM from my truck and disconnect the TM batteries with a switch that I added.

I have to remember to undo that when we leave, but since I always do a walk around inspection after every stop this is not difficult to remember.

Some TVs have either a relay or an isolating diode so that you need not unplug the TM. My Chevy and GMC do not have that feature.

Some people report that they are not able to provide enough power to the TM from the TV. This is frequently cased by the TV having too small of a charge wire or bad connections. Replacing the wire with a larger one and making sure the connections are good almost always solve that problem.

If you don't want to add a switch like Wayne and others have done, you can simply remove the main battery fuse......put it in your drivers seat as a reminder to reinstall it before pulling away......you emergency break-away switch won't work without the fuse in place.

[Wavery]

Btw..................

Welcome To The Tm Forum!!!:

[SCBillandJane]

It depends on your TV. You can see what I have. On a 9 week trip, I never unplugged unless we were unhooking to tour without the trailer or couldn't level the trailer while hooked up. I never ran it on gas while moving. We couldn't keep lettuce in the refrigerator because it was so cold. Ice remained frozen. We were in electric hookup sites almost all nights.

Our TV is a Honda Ridgeline and it disconnects the power to the TM when you shut off the ignition switch. It said that in the manual and I used a volt meter to verify it. When I tow I only use the 12 volt with the fan on. My TV seems to do a good job of keeping the TM battery charged and the refer keeps everything real cold.

I would guess the longest I have stopped with it running on the TM battery is a little over an hour in fairly hot weather.

[ShrimpBurrito]

It depends. But it's easy to determine. First, how many amp hours does your battery have? If you have a RV/marine deep cycle that looks about the size of a car battery, it probably has a capacity of around 100 amp hours. To prolong battery life, and also because your voltage will drop pretty by then anyway, you don't want to run the battery down more than 50%. That means you have 50 useable amp hours.

The fridge runs at about 10 amps, non-stop, whenever the switch is in the "on" position. So if you stop for an hour for a bite to eat, see the sights, etc., you use 10 amp hours, which is 20% of your useable battery capacity. Stop for another hour later in the day, and you've used 20 amp hours, or 40% of your capacity.

As far as the TM getting power from the TV, there seem to be 3 types of vehicles:

1) those that can run the fridge AND recharge your battery
2) those that can run the fridge OR recharge your battery, but not both simultaneously
3) those that cannot supply enough power to fully run the fridge; thus, the fridge consumes some battery power from the TM and some from the TV

I have a Toyota Sequoia, and a battery monitor on the TM, and I can quantitatively say the Sequoia falls into category 2. If I start with a fully charged battery, the fridge can be powered by the Sequoia as long as the Sequoia is running. When I stop, however, the fridge is powered by the TM battery, and since the Sequoia cannot recharge the battery and power the fridge, that power is permanently lost during the trip until I can plug in somewhere. For me, since we don't use hookups, a generator, solar panels, or even a large mouse wheel, that doesn't happen until we get back home.

Thus, I installed a switch accessible from outside that turns off only the fridge and the fridge fan. We use it if we stop for more than a few minutes. Pulling the main fuse isn't an option for me as it is located in the rear compartment on the SL models.

Dave

Originally Posted by ShrimpBurrito

Thus, I installed a switch accessible from outside that turns off only the fridge and the fridge fan. We use it if we stop for more than a few minutes. Pulling the main fuse isn't an option for me as it is located in the rear compartment on the SL models.

I don't have the SL model, but is is darned annoying to get to the fuse inside the strapped down battery box just to pull the fuse when I stop. That is why I installed a battery disconnect switch.

I have considered adding a separate switch just to disconnect 12 volts to the fridge and fridge fan, but have not found any value in the effort, so I abandoned that idea.

Interestingly my fridge cools better on 12V with the fridge fan OFF. I have #8 wire from the TV battery to the bargmann and I leave with TM batts charged. Must be there's more juice available by not running the fan. There must be enough wind while towing to circulate the heat out. I just keep the speed above 85mph.