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Topic: Circuit breaker for electrical bay cooling fan (Read 323 times) previous topic - next topic

Circuit breaker for electrical bay cooling fan

After popping the 2nd 350A fuse from the batteries to the inverter, I've also found this isn't helped by having so much heat in the electrical bay.  The small cooling fan that exhausts the hot air from the top of the bay, out the bottom, is locked up.

I've ordered a replacement and opened the junction box with the thermal switch, but can't find which circuit powers this.  Based on the schematics, it's supposed to be breaker 5, but that doesn't kill power to the junction box.  Anyone know where it would get it's power from?  It's 120V and comes in on Romex.
Keith
2003 U320 38' #6197

Re: Circuit breaker for electrical bay cooling fan

Reply #1 –
If nobody has the answer you can replace the fan by powering off the main circuit breaker or disconnecting power to the coach while switching the wires from the old fan to the new fan.
1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
prev. mh's 71 GMC 5 yrs. 73 Pace Setter 1 yr. 78 Vogue 5 yrs 81 FTX 40ft all electric 18 yrs. 1996 Monaco Signature 3 yrs.
2014 Grand Cherokee Overland
Dream as if you will live forever. Live as if you will die today.  James Dean

Re: Circuit breaker for electrical bay cooling fan

Reply #2 –
Keith, I just went thru that same issue and never found a designated breaker for that fan either. I did what Craneman suggested. Also, if your carful you could disconnect the wires one at a time and taping them up so there's no sparks.
Richard & Betty Bark & Keiko our Golden Doodle
2003 U320T 3820 PBDS
Build # 6215
MC # 16926
2016 Chevrolet Colorado 4X4 diesel

Re: Circuit breaker for electrical bay cooling fan

Reply #3 –
In our 2003, it was breaker #1 on the sub panel with the inverter circuits (at least according to the schematics). 

It kind of makes sense it would be powered by the inverter if you weren't on shore/generator, so maybe try shutting off all the breakers in that sub panel (if #1 doesn't do it).
Learn every day, but especially from the experiences of others. It's cheaper!  - John C. Bogle

2000 U320 36' non-slide / WildEBeest Rescue
2003 U320

Re: Circuit breaker for electrical bay cooling fan

Reply #4 –
If you are popping that 350 Amp fuse the problem is not just an overheated compartment. The inverter or charger should shut down on high temp long before that fuse fails. You have a serious long-term overload or a short circuit fault.
Dennis Haynes
Bohemia NY
2008 Nimbus 342 SE Carlyle
Build #6475
Motorcade #19148

Re: Circuit breaker for electrical bay cooling fan

Reply #5 –
Or a bad inverter.
2014 ih45  (4th Foretravel owned)
 1997 36' U295 Sold in 2020, owned for 19 years
  U240 36' Sold to insurance company after melting in garage fire
    33' Foretravel on Dodge Chassis  Sold very long time ago

Re: Circuit breaker for electrical bay cooling fan

Reply #6 –
It's been super hot here in Vegas.  Record heat yesterday at 120*.  2 weeks ago I added a 2nd portable A/C to help keep the coach cool inside.  That made two, plus the two roof A/C's.  In this heat, they all run.  The shore power comes from my detached garage which also has 2 A/C's and the pool pump running off of it.  All this off a 70A breaker from the house panel.

Last week all that load popped that 70A breaker 3 times.  2 of those 3 times it took out a fuse.  I'm thinking the inverter tries to catch the load when the shore power drops and the inrush is too high for the fuse.  This inverter is supposed to offer 6000w peak, but that much draw is like 500A from the batteries...which kills the 350A fuse.

My simple solution was to run an extension cord from the house (different circuit - not from the inverter) in the window and power the 2nd portable A/C unit.  No issues since.
Keith
2003 U320 38' #6197