| Check your wiring [message #340662] |
Tue, 05 February 2019 19:06  |
Tilerpep
Messages: 404
Registered: June 2013
Location: Raleigh, NC
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Senior Member |
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Here is a friendly public service announcement - check your wiring! For chafing, corrosion, previous owner or mechanic mis-wiring, any and ALL of it!
I'm replacing my Onan which was missing several key pieces when I bought the coach, so I'm going through pretty intently.
So, Coachmen ran heavy and not so heavy 12 volt wiring UNDER the coach. OK. But it's just winding through the frame with no retention straps, protective cladding, or anything. This coach has engine and house batteries up front, and a third Onan battery in rear (which has not been there since I've owned it). The main house trunk line (as shown in Coachmen wiring diagram on bdub site) goes from charger and fuse panels (interior over passenger rear tires), out the floor and under the back to the driver side with a "Y" at the generator battery and then up front. Factory manual shows a 50 amp breaker at the rear "Y", but it only protects the main line from the generator battery, and not the line itself from the charger. That seems wrong to me, but is the factory setup. Also there was a 50 amp GMC breaker up at the front from Coachmen factory. So there were originally breakers near each battery, but not the charger...?
http://www.bdub.net/wirediagrams/1977_Coachmen_26RB_Electrical_and_Plumbing_Drawings.pdf
Page 5 shows this "Y"
So here was my potential problem: 1. the 8 gauge main house wire chafed through more than an inch of sheathing at the 90 degree turn near the generator (bad enough by itself) and 2. The GMC factory 50 amp breaker up front had been upgraded to a modern thermal breaker - nice right? Not. The house wire to the back had been mounted on the same side of the breaker as the battery! The 12 volt feed to the fridge and the water heater were the only two lines being protected by the 50 amp breaker. (Do all Coachmen have this odd fridge/heater separate fused lines to the appliances?)
So please check your wiring for integrity, proper routing and general good practices for electrical load and mechanical stresses. Understand the original diagrams and intent of the engineers, and verify all upgrades and additions have good integrity - especially on high amperage lines! I have looked at that inherited miswired breaker for over a year, not until I was really learning the system did I realize the flaw.
1975 Glenbrook, 1978 Royale rear bath
Raleigh, NC
[Updated on: Tue, 05 February 2019 19:12] Report message to a moderator |
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