Wednesday, August 11, 2021

Travel Trailers Aren't What They Used To Be

 I'm not intending to write a lot about the trailer on the blog, but there are a number of similarities between cruising and camping (at least how I want to camp anyway).  So, I hope this provides some useful information as well as entertainment value as I write a bit about these experiences.

I spent way more time in marinas than I wanted while I was on the boat and I don't want to spend time in the camper at RV park type campgrounds.  What I've found is the modern camper seems to be setup to work best with "full hook-ups" (electric, water, and sewer connections at the camp site) commonly found in the aforementioned type of campgrounds.  Personally, I'd rather camp a little further away from the crowds...more like anchoring out on my own.

Back when I was a kid, at one point my family owned a small 16 foot travel trailer built sometime in the 60's or 70's I think.  It had a table that folded into the main bed, a bunk bed that folded down from the wall, a propane stove, a propane lamp, a small propane refrigerator, a small water tank accessed via a hand pump, and a small portable chemical toilet that slid out from a small cabinet when needed.  If you had propane in the tank, you really didn't need anything else other than enough room to park the trailer and you were set.  Yes, it was a more comfortable way to camp than backpacking (which I did as well), but it was still a somewhat rustic way to travel compared to what seems to be the current standard.

Stock picture of our trailer model.

Modern trailers have many more creature comforts, but they come at a cost.  Our new-to-us trailer has a fold down queen size murphy bed, a large, two basin kitchen sink, propane stove and oven, propane refrigerator two or three times larger than the old trailer, a microwave, air conditioner, propane furnace, a myriad of electric LED lights, amplified TV antenna and cable hookups, and a power retractable awning.  It also has a separate bathroom with sink, toilet, and shower.  The water tank is probably 4 or more times larger than the old trailer and no hand-pumping is required.  If it doesn't run on propane, it runs on either 12 volt DC or 120 volt AC power.

Since there is a 12 volt DC system, modern trailers can be used without hookups.  Unfortunately most come from the factory with a single 70 to 75 amp/hour lead-acid battery (a bit less than Rover's nearly 700 amp-hour battery bank).  So, realistically, there is only about 35 amp/hours of power available.  There is no inverter, so 120 volt AC items like the microwave, air conditioner, TV, or the 5 power outlets are of no use if not plugged in to shore power.  If there were an inverter, the microwave or air conditioner could easily deplete the battery in mere minutes.  As it is, the camper's parasitic draw on the battery (from the electronics in the refrigerator, propane detector, etc.) is a little under 1 amp, so a couple days just sitting can deplete the battery without even turning on the lights or using the water pump. What all this means is that my, and I assume most typical, campers can really only last a day or two without being plugged in to either shore power or a generator to recharge.

So, I made a few modifications to the trailer once I got it back to Colorado.

Realizing the battery power was insufficient, I replaced the standard battery with two 6 volt golf car batteries sourced from Sam's Club.  Wired in series, this boosts the 12 volt power storage from 75 amp/hours to 215 amp/hours.  The single battery box was replaced with a dual battery box. This upgrade tripled the usable power for around $200.

In order to stay someplace without power for longer than 3 days or so, increasing the battery bank wasn't enough.  The trailer came with a pre-wire for solar from Furrion.  The pre-wire is nothing more than a little bit of wire and a non-standard plug outlet (I assume they hope you will then buy their overpriced 100 watt kit).  I was able to find the plug and I decided to create my own foldable portable solar panel system.  Instead of the usual PWM solar controller sold with the kits, I was able to find a relatively low priced MPPT controller.  This means I could then efficiently use a higher output panel.  I created a 140 watt foldable panel kit that will charge the batteries significantly faster than the pre-made 100 watt PWM kits for about the same price.  I would imagine this setup would work equally well for a smaller sailboat or any other smaller solar power setup.

The solar controller mounted inside the trailer.

The solar panels setup at one of our campsites

Rear view of the solar panel "suitcase".
(carry bag not shown)

This takes care of the 12 volt DC power supply, but not the 120 volt AC one.  I had mentioned using an inverter, but even 215 amp hours of battery won't be enough to power an inverter to support power hungry items like microwaves or air conditioners for long enough to be useful.  It can, however, supply enough power for some smaller things like a TV, small fans, chargers, a countertop ice maker, or whatever.  So, I decided to install a 600 watt peak, 300 watt continuous inverter since it wouldn't use as much power (and I wouldn't need to run new wiring).  I was unable to find a smaller pure sine wave inverter with a remote switch, so I removed the on-unit switch and dual color indicator LED of the one I found and replaced it with an RJ45 connector that I then wired to a switch that had a dual color LED to create a remote switch that provides the red/green indications of the original unit.  The inverter was then inserted into the outlet circuit on the trailer with an automatic switch that will allow it to use shore power if available and the inverter if not (and the inverter is turned on).  

Inverter, modified with a remote indicating switch.

Now that we have a way to store more power and generate power, it made sense to have a better way to monitor the power available in the batteries than the simple 4 LED display that came with the trailer.  Instead of the expensive Victron monitors, we decided to give the AiLi/QWork monitor a try. It seems to work well.  I'm considering adding one to the boat.

The inverter and tank heater switches,
the master battery disconnect, and the battery monitor.

There were a couple other modifications as well.  The first time we used the camper was late last fall and the trip was cut short because we ran into sub-freezing temperatures the last couple nights.  I don't know that the tanks would have frozen, but the lines might.  To prevent this in the future, we added a tank heater and some insulation to the fresh water tank lines.  We figured a jug of RV anti-freeze in the waste tanks would be sufficient to protect them, but you can't do that to the fresh water tank.  For a creature comfort feature, we also added a MicroAir Easy Start that allows the air conditioner to be run off of a small 2300 watt inverter generator.  One final addition was a master battery disconnect switch similar to what is found on most boats.  This way I could disconnect the battery bank to prevent discharge while it was parked in storage.

So, just like the boat, it didn't take me long to start customizing the trailer to better suit our needs.  If anyone is interested in any of the details on these projects, let me know and I'll try to post additional information.