Saturday, June 26, 2010

Rippling RV Refer

While running the refrigerator on LP it will light and run but only for a short while. I did the normal cleaning of the burner, the burner jet, the ignitor. I did a test for dirty power at the DC terminal block even though it’s on the LP mode. On the AC scale I read about 6-volts or less at the connection. Is this correct? Could my converter be faulty? I tested it while plugged into shore power. I have a 45-amp power converter with a charge wizard.
Joe, (McKeesport, PA)
 
Joe, though you didn’t specify the brand of refrigerator in your motorhome, I believe you have a Norcold. Excessive AC ripple can indeed cause the problem. In order to verify that this is the case, make sure the house batteries are fully charged and in good condition and then disconnect the AC shore power to the coach. This will remove the AC source and therefore the ripple. The refrigerator should function normally on the propane mode and powered by the batteries. If you continue to have this problem with the camper running strictly on 12-volts only, the problem lies elsewhere. In this case you should suspect faulty or loose connections, faulty or intermittent gas valve, flame sensor, low propane gas pressure or a faulty control board. 

I’ll assume the LP container has fuel. If the unit operates properly, then we can assume the problem is indeed AC ripple. The first check is to make sure the refrigerator is connected to the filtered side of the converter output. If it is connected to an unfiltered output, excessive ripple is likely to occur. On the fuse panel, some of the circuits will be filtered and some will be unfiltered, these should be indicated on the panel labeling. Identify the wiring for the refrigerator and ensure that it is connected to a filtered output circuit. If not, swap it with a “non-critical” circuit and run the operating test once again. If the refrigerator is connected to a filtered circuit, there could be a problem with the filter in the converter and further troubleshooting of that device should proceed.