Fun Finder Solar Install Part 4

jbfunfinder · 01-29-2015, 11:01 AM

This is a follow-up post to my three former where I told the story of one FF owner's experience installing a roof-top solar system and new battery rack. We are back from a January trip to Quartzsite, AZ where we joined literally thousands of other RVers dry camping on BLM land for five days. I noticed many other solar installations as well as a few portable units as we wheeled around among the miles and miles of campsites. As we all know, this time of year, even in the sunny Southwest, the sun is low on the horizon. I chose to do a flat roof-top install of my 100 watt panel out of convenience. This is far from ideal positioning, especially for this time of year. I did see a couple of dozen snowbirds (ones probably there for the November through March "season" who had built-in tilt frames under their panels. I am imagine they were able to harness the sun's energy more efficiently. My battery storage meter read 100% on arrival and typically read around 45%-55% each morning when we turned on the propane furnace (with electric fan) to warm the interior. Outside temps at 7 AM were between 32 and 45 balmy degrees so it is not like we were having to run the fan for any substantial amount of time. Other draws on the batteries were water pump and lighting, but nothing substantial. After off-roading all day on a very clear and sunny day, the meter read 85% charged. Cloudy days only produced 70% charge. So I am marginally disappointed. Looking on the bright side, I am looking forward to the sun being higher in the sky, and I know I can always install a tilt frame under the panel, and I could add another panel.
By the way, our friends who were with us in a 21' Lance with a GoPower 160 watt flat roof panel, experienced charge percentages around 10% higher, but never made it to 100% as they did daily this last summer when we were camping with them in a sunny campground site in Sequoia National Park.

shadow · 01-29-2015, 06:12 PM

there are a few simple things you can do if you have not already done so. Install LED bulbs throughout the trailer. Make sure your panel is clean, takes very little dust to cut the efficiency by 30-50%. Given where you were at dust is kicked up alot one of those California car dusters works great. When out cut the power to the trailer, this will kill any parasitic drain, I presume you have your solar panel wired direct to your batteries via controller. If your going through the converter then your losing more efficiency.

jbfunfinder · 01-29-2015, 08:22 PM

Thanks for the tips, Shadow. I have never thought about pulling the battery disconnect when leaving the trailer for the day. There certainly are some "electricity vampires" in our trailer. The one concern I would have is the spark igniter for the propane frige. Come to think of it, the Dometic frige is actually dual propane/120 v unit like most of us have. I need to look into how the igniter works when not plugged into shore power. Anyone out there know??
We do have LEDs inside and out and yes, the panel is connected directly to the batteries through an MPPT charge controller and I have not even considered an inverter at this point.

shadow · 01-29-2015, 09:27 PM

the fridge wont run with power off, but shutting down for a few hours shouldn't hurt anything unless you have the ice maker. Another trick is the fridge has a heating element in the seal, only useful in cold really humid climates help reduce condensation, it draws a fair amount of power. I disconnected mine 2.5 years ago and have had no problems with condensation and made a noted difference in parasitic drain. try the leds and seal heater, forget about turning master power switch off and see how that works. On my fridge the heater power line is accessible in the fridge light, I just cut the power wire, check the manual to make sure you find the right color

**LJAZ** · 01-30-2015, 06:59 AM

Many of the Dometic fridges have a switch to disable that heating element. In the manual it's identified as the climate control system. You may have to hunt for it though. It took me a while to find it on mine and the manual was pretty vague on the location. On mine it was a small rocker switch recessed into the bottom edge of the control panel.

In my part of the world condensation is rarely a problem so I don't need that feature at all.

jbfunfinder · 01-30-2015, 12:10 PM

Thanks all for the suggestions. Our refrigerator is the very basic Dometic 2652 with none of the extras like ice-maker, low ambient control switch, and climate control switch so we can strike that off the list.

profdant139 · 01-30-2015, 04:27 PM

Jb, do you have an accumulator on your water pump? That could save you a lot of power right there -- the pump runs for a much shorter time. Plus it is quieter. Installing it is a very easy project.

jbfunfinder · 01-30-2015, 07:04 PM

Excellent idea. Coincidentally, my wife and I were grousing with each other about the loud and oscillating pump on our recent trip despite it being new. My one year old previous pump died on me and I replaced it last summer. As I ordered it on Amazon, I saw that other also bought accumulators at the same time. Since I knew little about their function and advantages, I did not order one. Looks like now would be a good time. Thanks for the tip.

**LJAZ** · 01-31-2015, 10:14 AM

Quote:

Originally Posted by jbfunfinder

Thanks all for the suggestions. Our refrigerator is the very basic Dometic 2652 with none of the extras like ice-maker, low ambient control switch, and climate control switch so we can strike that off the list.

I have the same model. No ice maker and no ambient control switch, but it does have the climate control switch. It's just really well hidden. Took me quite a while to find it.

jbfunfinder · 02-04-2015, 12:02 PM

LJAZ
I unsnapped the control panel above the refrigerator (the plastic bar that runs across the top of the unit above the freezer) to inspect it from the back. There is no rocker switch. However, I discovered a "heater cable" (part "k") on the wiring diagram for the refrigerator which is a label affixed to the back of the refrig behind the outside cover. I also found two red and two black wires that run from beneath the black "power module" cover upward. These appear to be the wires for the interior light bulb and for the heater cable since I found the same looking wires inside of the interior light unit after pulling off the clear diffuser. Thank you Shadow for pointing this out. I will get my continuity tester out and check the circuits before I do anything.

Bottom line, thanks LJAZ for helping me eliminate one more energy vamire. As you pointed out, the refrigerator does have a 1/2 amp climate control heater which certainly can be cut or switched.

Another discovery, Dometic apparently does not print new manuals each time they make changes to wiring on a particular model, ie., following the decision to eliminate the CC switch. The manual which came with my TT just says "DM2652" There isn't one for a "DM2652-LBX"....

hotqld · 02-06-2015, 05:17 PM

We started with a 200 watt panel, 6 months later put another in that was good except winter it was borderline.
Now we have 3 panels 600 watt, and see often the controller pumping in 20 -30 amps.

Also consider portable panels for winter wire them into your existing controller.