Perplexing Propane Problems
Dear RV Doctor:
I am having a problem with the pilot light on my motorhome’s hot water tank. I can light the pilot, but when I turn the dial to the “On” position, it takes a moment for the ignition. And when the propane gas finally reaches the pilot light area, the combustion is so strong that it blows out the pilot light and the main heating flame.
My motorhome also has a Norcold refrigerator that can operate on AC, DC, or propane. When propane is selected, once the pilot is lit, the refrigerator begins to cool automatically depending on the temperature level that’s set. I can light the pilot flame, but after that, nothing happens. The pilot light just stays on and doesn’t ignite a flame to cool the refrigerator.
I believe that both of these problems are related, but I am not sure what’s causing them. The hot water tank is near the front of the unit, whereas the Norcold refrigerator is at the rear on the same side as the hot water tank. I would appreciate any advice that you can offer in solving my problem.
Dan Howell, Michigan
Since you have an older motorhome, I suggest that you have a service tech perform a timed pressure drop leak test on your propane system, and also check and adjust the pressure regulator to the correct setting. Accomplishing this takes special equipment to measure and set the pressure, and to test the regulator, so, unfortunately, this is best left to the professionals. The delivery line pressure of the propane must be set to 11.0 inches of water column.
As far as other possible causes for your propane appliance problems, here are a couple of things to consider, starting first with the water heater. There will always be a brief delay from the time you move the control valve from “Pilot” to “On” before the main flame ignites. The propane has to travel from the control valve, through the orifice, and down the mixing tube before reaching the pilot flame. The alignment of the mixing tube is crucial. As the gas flows through the tube, it draws in fresh air to combine with the propane before the mixture is ignited. If the tube is not centered on the orifice fitting at the control valve and in line with the angle of that fitting, then turbulence will take place inside the tube and create an improper mixture for combustion. This can cause the pilot and main flame to be extinguished. Plus, the pilot flame should encompass only the very tip of the thermocouple. A pilot flame that is too large or too small also can lead to pilot outage.
On the refrigerator, the standing pilot flame will remain small until the temperature inside the refrigerator rises above the thermostat setting. If the box is already cooled, the pilot flame will not ignite the main burner until you open the door a couple of times or put warm food inside. Now, if the box is already warm and the main flame will not come on, chances are the thermostat capillary tube is mispositioned or the thermostat has lost its charge, necessitating a new thermostat. A few tests by a competent certified service technician will quickly reveal the exact cause.
Refrigeration Swap
Dear RV Doctor:
We attended the last FMCA convention and went to your seminars. We are planning on swapping out the absorption refrigerator in our Newmar Essex motorhome and replacing it with an all-electric residential refrigerator. My question is, will the Xantrex RV2012 inverter, which is a modified sine wave output unit, work on an electric residential refrigerator when traveling? We have added two extra batteries and have the cabinet space necessary, though we will have to move the refrigerators in and out through a window. A Xantrex representative said there’s a 99 percent chance it would work but didn’t seem as confident as I would have liked. Any other suggestions about this project would be appreciated.
Tom Chelbana, F117995, Moreno Valley, California
The first thing you need to determine is whether the refrigerator you’ve chosen will run properly on a modified sign wave inverter or will require a pure sign wave inverter. It’s been found that some electronics with microprocessor controls experience problems when operating on modified sign wave current. Check with the refrigerator manufacturer to find out whether the refrigerator in question will have any trouble running on modified sine wave current.
I have heard of some operational issues with the RV2012 inverter while powering high-current loads, so it probably boils down to simple math and how much wattage the refrigerator will actually require. Should you encounter problems with the RV2012, perhaps a move to a pure sine wave inverter might be a recommended upgrade.
In some cases, especially if the inverter installation has less than optimal ventilation, heat buildup in the inverter can cause disruptions. I’m assuming you have a remote panel as well. Be sure to monitor the battery capacity and how long you can safely power the refrigerator at that load level. Keeping track of this is possible on the remote panel. But it all depends on the brand and model of the residential refrigerator you choose.
Keeping the inverter cool and the batteries charged will certainly help as long as the demand of the refrigerator is less than the average output of the inverter. You might consider adding a dedicated inverter just for the refrigerator. At a recent RV show, I saw quite a few large motorhomes equipped with two inverters, a huge battery bank, and a residential refrigerator. The only propane device on the coach was the cooktop.
Simple Solar Charging
Dear RV Doctor:
When winterizing my motorhome last year, I took the batteries out and stored them in my garage. I have a small solar battery charger. Is it okay to charge the batteries during the winter using this small solar charger? It’s a very small charger, one used to charge a vehicle battery through the cigarette lighter during the daytime.
John Lowther, New Brunswick, Canada
I’m not a big fan of those simple plug-in solar charging devices, especially for deep-cycle RV batteries. As long as you fully charge the batteries prior to removal and store them in a clean, dry area, there’s no need to do anything until you’re ready to prepare for that first trip come spring. Of course, once the batteries are out of the motorhome, you should be able to easily monitor their status and recharge during the downtime if needed.
I’d be hesitant to connect any battery charger that does not have a voltage regulator during storage “” especially a small, uncontrolled solar device “” unless you are there to monitor the charge voltage and the specific gravity on a weekly basis. Some less-expensive solar chargers do not possess the sophistication or the technology to safely avoid the damaging effects of overheating and/or overcharging.
My advice is to fully charge the batteries; store them; and then clean, rehydrate (if necessary), and fully charge the batteries again after the winter. Follow these steps and they should be fine. All batteries will self-discharge over time, which is why starting the downtime with fully charged batteries is always recommended. If you have a battery charger and 120-volt-AC power available, it’s not a bad idea to occasionally recharge the batteries throughout the winter.
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