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I have an '89 with a 20 gal Raritan 120V water heater; and the switch inside the coach (kitchen) just went bad. It physically broke internally. I'm trying to figure out how to get the heater working again as we begin our trip from Maine to Florida tomorrow. The switch in question is a Carling rocker switch, rated at 125V 16A. I have tried replacing it with a similarly rated Taiwanese switch, also having three spade prongs in the back. The numbering system on the replacement is reversed from top to bottom, 3,2,1 instead of the 1,2,3 on the old Carling switch. I have tried reconnecting the wires both ways, 1,2,3 and 3,2,1 with no luck. I would be satisfied just connecting the wires together with a wire nut and leaving the heater permanently on, since I could flip the circuit breaker if I needed to turn it off. However, I am confused by the fact that there are three spades in the back instead of only two. I don't know which is which: which one might be for the internal light in the switch, or a ground, or what. We are beginning the trip on a Sunday. Since the new switch hasn't worked, and I'm unsure about the wiring plan for the switch, I will just rely on the engine heat to warm our water unless someone can advise me on a way to bypass the switch. Thanks in advance for any help you can give. - Dick Quirk
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It looks like we have it running after all. I would like to understand the reason for a third terminal on the switch, though. Just in case I run into a similar problem in the future. Dick
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Typically, illuminated switches need a third pole to activate the internal light. A standard, non-illuminated switch breaks the power leg of the 120 volt power source and reconnects it when turned on. To have an operational light, you have to also have the neutral leg of the power source going to the switch. While I am not sure that all manufacturers use the same numbering nomenclature, all least some that I have seen use 1 as the hot (or incoming power), 2 for the load and 3 for the neutral. Frequently, the wire that goes to the 3 pin is a double wire, one from the incoming power source neutral and the other going to, in this case, the water heater neutral.
You can use a VOM set to resistance to see if 1 and 2 go from an open circuit (very high resistance, typically pegging the meter) to a closed circuit (close to 0 resistance) when the switch is moved from OFF to ON and then with nothing attached to terminal 1, if there is a constant resistance between 2 and 3 regardless of the position of the switch. This would be consistent with the nomenclature in the previous paragraph.
Michael Day
1992 Newell 43.5' #281
NewellOwner.com
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Thank you Michael. That all makes sense. I do have it working at present. I believe the light is 12V; is only flashes for a split second when I turn the switch off; but the water heater is heating water. I will go back and run the test you described at earliest opportunity. Thanks again
Dick Quirk
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on my 90, the hot water rocker switch was illuminated and was a 120v light/switch. they do not run a separate 12v line to the switch and you will see there is not enough blades on the back for it.
tom
2002 45'8" Newell Coach 608 Series 60 DDEC4/Allison World 6 Speed HD4000MH
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As a general rule, low voltage (12/24v) and high voltage (120/240) are never run in the same conduit or share spaces. NEC Code.
James Tuckness
