Norcold N300.3 Refrigerator This article is taken from the Winnebago Rialta Owners web site with the permission of the site owner. It has been modified to remove motorhome-oriented terminology, and insert TrailManor-oriented terminology. The scattered parts have been re-united and organized. And the Table of Contents has been added.
Part 1 - General Information: model N300.3 refrigerator in every trailer model. The “.3” suffix on the TM installs a Norcold model number indicates that it is capable of running on three different power sources: propane (LPG), 12 VDC, or 110 VAC.
A DC fan may help improve refrigerator performance when the refrigerator is not installed in accordance with Norcold's installation requirements or when operating the refrigerator in high ambient temperatures (see "Refrigerator Installation Manual.") A DC fan will assist in providing the necessary amount of airflow.
Is this myth still true? The Stated Requirement: The manual for the Norcold refrigerator says that its "operational limits are 3 degrees off-level side-to-side and 6 degrees off-level front-to-back, as looking at the front of the refrigerator".
Let's first take a look at the wheels and visualize the variation from level that would still allow the refrigerator to operate properly. Conclusions: 1. The TrailManor trailer can out of level side-to-side (wheel-to-wheel) by as much as 9.5 inches without exceeding the refrigerator spec of 6 degrees.
And after viewing those sketches, you are probably asking yourself "Why bother leveling at all?" Well, Norcold states the answer simply as "Normal vehicle leveling to provide comfort for the occupants is satisfactory for refrigerator operation".
Usually either of the two electrical modes of running the refrigeration unit are problem free. The unit either gets power to heat up the ammonia gases to work properly, or it doesn't. Norcold stipulates the requirement for AC voltage as between 108-132 volts. The requirement for DC voltage is between 11.5-15.4 volts.
The usual result is that the propane flame will light, but will not stay lit. If you write to Norcold, they will send you two wires with new connectors on the ends. A simpler answer is to pull each connector off the blade, squeeze it closed with a pair of pliers, and replace it on the blade.
Photo #2 2. Open the valve on the propane tank. 3. Turn the thermostat to its coldest or highest setting. 4. Turn the selector switch on the control panel to the gas position 5. Push and hold the safety valve button in the fully depressed position. (NOTE - This "safety valve"...
Photo #3 Once you see a flame present, have the person on the inside continue to hold the button on the safety valve for about 30 seconds. On a properly adjusted burner assembly, you would normally need to hold the safety valve in for only a few seconds. The purpose of this extra time during this troubleshooting procedure is to ensure that the thermocouple is being brought up to full temperature.
Photo #4 Gaining access in order to remove and re-install any of these items with a screwdriver in this cramped area may be difficult. Stubby screwdrivers are of little use because they generally have big, fat handles that prevent them from being in the correct alignment with the screw to be removed.
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Photo #5 The tip of the thermocouple will be discolored due to heat from the flame and this is normal. However, the tip should be uniform in shape, not distorted, and without any particles or debris clinging to the end. Use the fine emery cloth or green scratch pad to thoroughly clean and smooth the tip.
Photo #6 If the bracket is bent or distorted and the tip of the thermocouple just barely touches the flame or doesn't touch it at all, then it will not be brought up to full temperature and therefore no signal to signify the presence of a flame will be generated.
Photo #7 Once the igniter is removed from the burner box, use a fine piece of emery cloth or granite sandpaper to clean the end that normally sticks into the flame. This end will normally be discolored from the heat but try to make it as clean as possible without any debris or particles being burned onto the tip.
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Photo #8 Photo #9 Once the burner orifice assembly has been removed from the burner box, examine the gas outlet slits that are cut into the metal. Soot and other debris may eventually build up here blocking one or more of the slits. In Photo 9, note the debris and small particles around the slits, especially the slit closest to the mounting flange.
not use a pin or wire to poke into the orifice tube. You can fill up a small drinking glass with alcohol and allow the burner orifice to soak for several hours if there is any build-up of soot or carbon.
I called Lichtsinn’s and they had a replacement Thermocouple – Norcold part number 619154 The cost was $25.95 with their summer discount of 5% [winter discount is 10%]. The part arrived a few days later via UPS to my door.
120 volt supply cord from the receptacle on the left. The 12 volt wires were removed from the terminal block (yellow and white wires). I turned the gas valve that is part of the refrigerator to the “OFF” position. I removed the two lock nuts on the bolts that fasten the refrigerator to the hold down brackets.
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the interrupter and pulled the TC out of its position. I was then ready for the installation of the replacement TC.
New Thermocouple Installation I uncoiled the new Thermocouple and straightened it out to its full length….54”. I inserted the probe end into the burner box and routed the rest of it similarly to the old one and positioned the upper end near the interrupter so that I could thread it into the interrupter opening. I snugged the fitting gently but firmly.
Cleaning And Repainting The Rest Of The Mechanism At this point, you have installed the new thermocouple and are ready to re-install the refrigerator. However, take a good look at the back side. As long as you have the entire thing out and sitting on the bench, why not consider doing a complete maintenance of the burner and heating tube assemblies and at the same time, cleaning up some of that rust so the thing will look new again.
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Take a good look at these two pictures. This is the same identical refrigerator but only one day later, after the black metal parts were cleaned of the surface rust and a new coat of paint applied. OK, what's so important about having a nice black shiny paint job on the parts of the refrigerator that you don't even see? These parts are painted black for a reason: heat transfer.
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To accomplish this refurbishment, a lot depends on just how detailed you want to get. To be done thoroughly, you will need to remove the insulation around the heat pipes and chimney. There you will also see the actual 12V heat element and the 110V heat element. Both can be removed and a little emery cloth used to shine up the working end of the heat elements.
cleaned refrigerator, it'll bake the new paint as it heats up so it sort of smells just like a new one. Another Cleaning Idea Here's a tip from another owner whose fridge did not work at all on gas and barely got cool on electric: These old absorption units can be real troublesome if not kept clean and mine was full of rust so I removed the burner and cleaned it.
Putting the refrigerator back in the trailer This was basically the reverse procedure of removing it. After it was positioned in the cabinet, I connected the two tie down bolts in the back first and then reinstalled the screws around the front of the cabinet.