Today’s project was installing some aftermarket electronic wizardry into our rooftop air conditioner to trick it into operating reliably. It hasn’t worked as expected since we had our solar power system installed, shortly after we bought the trailer, more than four years ago.
We’ve managed to get by mostly without functional air conditioning by camping in cooler weather or higher elevations. And since we prefer to camp away from utility hookups we knew we really wouldn’t be able to power the air conditioner, even if it was working.
That all changed when the COVID-19 pandemic severely limited our travel options. When it worsened, we knew we needed to able to boondock on our own property. And that was quite difficult during a long string of days when the afternoon temperatures were in the high 90s.
Always cut the blue wire
The problem is that the air conditioner draws a tremendous amount of power when it starts up. Once it is running it gets by on a lot less power, but getting going is often impossible.
Our rooftop solar system includes a 2000-watt inverter. That’s the device that turns the DC power from the batteries into the AC power that things like the refrigerator and air conditioner need. Even when we are connected to shore power that should be able to deliver 30 amps the power flowing through the inverter will trip its internal circuit breaker if the demand is too great. And that’s what was happening nearly every time the A/C unit tried to start up.
So I climbed up on the roof of the trailer in the hot sun and installed a little box of electronics inside the air conditioner housing. According to the instructions, and lots of content from other RVers I found on the web, this device sort of spreads out the big load of starting the air conditioner compressor. This should reduce the peak load enough that it doesn’t trip the circuit breaker on the inverter.
What’s that dead horse trope about how to disarm a bomb? Is it “always cut the blue wire”? The installation instructions for this aftermarket electronic wizardry actually read “Cut the blue wire.”
I cut the blue wire, stripped insulation from a few others, connected some terminals, and hoped for the best.
The aftermarket A/C wizardry is so smart that it needs to learn how our A/C unit operates. It does this by having us put the system through a carefully scripted series of start-run-off cycles, five times. The magic box then understands the quirks of this individual air conditioner and is able to manage the start-up process to avoid tripping the circuit breaker.
Unfortunately, that five-start learning experience needs to occur while the RV is connected to a reliable shore power source.
So we left our property and checked into a local casino RV park for a few days. After getting the trailer parked and settling in, we ran the five-start procedure. Our equipment seems to have learned to play well together. We’ve been running the air conditioner all day, with no issues.
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