Oven Won’t Shut Off
Dear RV Doctor:
We have a 2001 Holiday Rambler. The stove is the original Atwood Wedgewood, which measures approximately 20 inches wide by 18 1/2 inches deep. When the oven reaches the set temperature, it does not stop or shut off; it just continues heating. I can get the oven flame to turn off by reducing the set temperature. Any thoughts? Are replacement parts required?
Lucille Lorenzano
Via email
The oven thermostat turns on and turns off the oven flame. The thermostat monitors the oven temperature by means of a thin, pencil-like sensor at the back of the oven, most likely in the upper reaches on the back wall. The sensor is attached by a clip of some sort and must be suspended in the air somewhat.
Over time, it’s possible for cooking oil, grease, and even oven cleaning products to coat the temperature sensor and adversely affect its accuracy. Check to be sure the sensor is clean and not touching any other metal component in the oven. It is connected to the thermostat through a very thin capillary that is quite fragile. Look for kinks or breaks in that capillary tube, which runs from the temperature-sensing bulb up to the thermostat. Be very careful handling the sensor so as not to damage its capillary tube.
Unfortunately, the oven temperature bulb cannot be replaced apart from the entire thermostat. If the sensor is clean and suspended properly, and there are no kinks in the capillary, it’s likely the thermostat assembly will have to be replaced. Contact Atwood for locations of their service centers. It is best to have a certified service tech replace the thermostat assembly rather than attempting it yourself. Let’s just hope it’s a fouled temperature sensor that can be cleaned easily!
Source Voltages
Dear RV Doctor:
I have questions about electricity. What voltage can I expect to receive from RV parks: 240 volts or 120 volts, or does it vary? If I feed 220 volts to my coach, will the converter step it down to 120-volt usage? Or should I not do that? If the source is 220 volts, does the feed split to different supplies on the coach, such as one leg to one side and another to the second air conditioner, for example?
Mario Funicelli
Via email
Most modern campgrounds have spaces with both 50-amp and 30-amp receptacles, while others may offer just one or the other. Any 50-amp service provided by a campground pedestal should be delivered at 240 volts AC. In some cases, it may be 208 volts (I won’t bore you with those details here). For a 30-amp receptacle, it should always be 120 volts AC, plus or minus 5 percent.
If you have a 30-amp motorhome, you can safely plug in to a 50-amp receptacle by using a 50-amp-to-30-amp reducing adapter. This, however, should be a last resort.
If you have a 50-amp coach, it is preferable to plug in to a 50-amp receptacle. You also can plug in to a 30-amp receptacle using a 30-amp-to-50-amp adapter, but you’ll likely lose the use of some electrical devices, or at least the ability to operate them all at the same time. The 50-amp receptacle will measure 240 volts across the two hot legs, but it is delivered in two separate legs of 120 volts AC each, both at 50 amps.
It is very rare for any RV appliance to run on 240 volts AC. The converter will be connected to one of the 120-volt-AC legs, since it is a resistive load itself. The heavier loads — air conditioners, microwave, heating elements, etc. — indeed will be split as equitably as possible between the two legs. No step-down transformer is involved, since it is simply two 120-volt-AC legs on opposing phases.
The Cold Appliances
Dear RV Doctor:
We are new to RVing and recently bought our first used Type A motorhome. Air-conditioning will be important, or at least it will be to the kids in the back. Can the rooftop units be run while we drive, and if so, do we have to run the generator to power them? Or should we try to cool the whole coach with the dash unit? I have safety concerns about running the generator while traveling, and I’m not sure whether the engine alternator can keep up with the drain on the coach batteries from two rooftop units.
Another question is about our refrigerator. When we had the unit inspected by an RV tech before purchasing, it worked fine. Later we took the motorhome out, and there was no power to the refrigerator’s front control panel. Is there anything simple that I can check before I spend money getting another tech to look at it?
Tom Thatcher
Seattle, Washington
The roof air conditioners operate only on 120 volts AC; therefore, you must either plug in to shore power, run the generator, or perhaps power one air conditioner from an inverter. The engine alternator can charge the coach batteries only while driving. It cannot power the air conditioners, since it produces only DC current, not AC power.
You can at least try the dash A/C first. If it proves insufficient at cooling the whole coach, then run your generator. It is okay, in most instances, to run the generator while driving. However, your fuel mileage will suffer when running both the generator and the engine.
Another thought is to install a battery-powered evaporative cooler in place of one of the roof vents. Get the coach good and cold while plugged in to shore power, and then use the evaporative cooler while driving, since it operates solely on 12 volts DC. The engine alternator should be able to keep up the charge rate on the battery bank while driving.
As far as the refrigerator, the circuit board that powers the control panel has fuses. To find them, you might have to remove a cover from the circuit board through the exterior access. Check whether one or more fuses have burned out. If necessary, send me the exact model number of the refrigerator and I’ll dig further. But I’m guessing it is something as simple as a blown fuse.