Control board not working? Replace it!

By Russ and Tiña De Maris

Perhaps some of the most mysterious of RV technical issues surrounds electronically controlled appliances. “Back in the old days,” as some of us recall, we didn’t have fancy control boards on refrigerators, furnaces and water heaters. Of course, “back in the old days” a lot of us had to go outside in the cold or heat to light off those selfsame appliances.

Nowadays, the trouble is when things start getting “buggy” it can be difficult to track down the problem. One time, one of our 3-way refrigerators, which had been a straight-A student, suddenly went rebellious on us. Sitting on a hot parking lot just outside of Old Mexico our refrigerator stopped being a chill box and the threat of global warming parked itself right in the middle of our kitchen. Only by turning on the generator and resorting to “shore power” would we get any chill in the box. Gas didn’t light, and DC simply knocked all the low-voltage power out throughout the rig. We cut our time in the field short and headed back to base camp.

Dino to the rescue
In a safe harbor with another working fridge available we started down through the diagnostics process. The whole works pointed to a control board failure, or so it seemed. We contacted an RV refrigeration supplier who opined that it “sounded like” a board too, but he couldn’t really be sure without running tests on it. Too bad he was 1,500 miles away. So we called the horse’s mouth or, should we say, the Dinosaur’s mouth.

Yep, when campfire talk comes around to appliance control board problems the name probably mentioned most is Dinosaur. Built by a seemingly obscure company, Dinosaur boards are the leading word in replacement control boards. The Dino folks build replacement boards for just about every RV appliance (and generator) application there is. We called in and immediately tied into one of Dinosaur’s tech fellows. After an initial discussion of the problem the technician asked if we wouldn’t mind checking a couple of things “in situ,” right on the back of the refrigerator. The Dino-tech walked us through a series of tests with a digital multi-tester that verified our refrigerator control board was ready for the scrap pile.

To his credit, in addition to making a suggestion for a given Dinosaur board, the technician did suggest we could try an OEM replacement board. Maybe there was a bit of tongue-in-cheek here because the old “pudding covered” board out of the back of our ‘fridge was “out of production” from the reefer maker. That’s a common complaint among RVers: Many control boards aren’t “replaceable” with OEM boards. It’s a case of, “Well, we’d be happy to direct you to a dealer where you can by a new refrigerator, furnace, water heater,” etc.

Replacement boards do cost money, but it’s still a whale of a lot less expensive than replacing an otherwise “good” refrigerator. In our case the Dino-made after-market board is really superior to the OEM. We peeled back the old epoxy “pudding” that covered our dead board and discovered components that had actually come unsoldered from the old board. A circuit board is basically a plastic plate over which circuits between components are etched out of copper. Where components were soldered into our circuit board, the component itself resides on one side of the board and its electronic wire leads are pushed through the board and soldered onto “traces” on the underside. With heat and vibration the solder joints are subject to stress and often break. In Dino’s replacement boards the leads go through a hole in the board that is copper plated from front to back. As a result a much more skookum solder joint is possible.

Long story short, we bought a Dinosaur replacement board. It arrived soon, along with full instructions on how to replace the old board with the new. Let’s walk through it:

Putting in a new board
First the disclaimer: Dinosaur’s website plainly says that RV appliances use LP and recommends that trained technicians do replacement work. In fact Dinosaur will only sell to retailers, rather than to end-users. If you replace your own board make sure you understand the risks. If you hire the work done, don’t throw away Dinosaur’s phone number – their staff can still help you sort out problems that can save you money.

Since not all control boards are alike, we offer generalized tips for replacements. Be sure to follow the instructions that come with replacement boards to the letter if you decide to do your own work.

First, turn off the power! Unless the instructions say otherwise, having the “juice” off is just a smart safety issue. Turn off both shore power and disconnect the RV “house” battery. Remember: When working with electrical stuff, take off your jewelry.

If there’s any question about the wires coming off your existing control board, mark them. We had several of the same colored wires on our board, three of the same color right next to each other. Tagging them with tape is one option. Count the number of pins on your existing board and note the colors (or other identifying marks) of their associated wires.

If there’s enough room in the appliance compartment, detach each lead one at a time and put that lead in place on the new board before proceeding to the next. If not, here’s where the importance of identifying each wire comes into play. You’ll find it much easier to use needle-nose pliers to disconnect and reconnect terminal leads. After you’ve completed the job double-check your wiring connections before turning the power back on.

We were thoroughly gratified that within a couple of seconds of pushing the “power on” button, the popping sound of the gas burner lighting came to our ears. Sure enough, all it took was a new board and our reefer was back in business.

Getting help from Dinosaur
Dinosaur Electronics has both a full website and a telephone support staff. Before you call to ask for troubleshooting assistance or an application have this information ready:

1. The specific problem. Be as detailed as possible with a step-by-step rundown of what happens (or doesn’t happen) with your appliance.

2. The manufacturer and specific model number of the appliance. You may have to hunt around for this information for some appliances, but without it your help will be limited.

3. You may be asked for certain information to help troubleshoot. Having a cordless telephone or cell phone really helps. If you have a digital voltmeter make sure it’s at hand and have the cover off the appliance to facilitate getting at your control board.

Dinosaur Electronics can be reached by phone at 541-994-4344 8 a.m. – 5 p.m. Monday through Friday, Pacific time. They also maintain a web-based “customer help form,” where you can enter and e-mail technical help requests. All that information, and a great deal more is found at Dinosaur’s website.

##RVT947