Forum Discussion

yankee_camper's avatar
yankee_camper
Explorer
May 02, 2015

Keep blowing fuses ?

I just installed 2 fans in the stack of my refer to aid in cooling. Everything went well until I connected to a toggle switch to manually control the on-off function of the fans. Without the toggle the fans run as they should but obviously I don't want them running 24/7,but the minute I hooked up to the toggle switch and turn it on "pop" goes the fuse.Thinking it might be a bad switch I tried 2 others-all brand new and with the same result.? Anybody have any ideas where and what to look for?

26 Replies

  • Gene_Ginny's avatar
    Gene_Ginny
    Explorer
    May 04, 2015
    westend wrote:
    Well, I guess I'm confused by this:
    Well, the switch almost worked. I did turn the fan off .... after the fuse blew.
    ....
    Tongue firmly planted in cheek when I posted that. ;)
  • jrnymn7's avatar
    jrnymn7
    Explorer
    May 04, 2015
    Perhaps a dual fan set-up would work well, in that case?

    One continuous, or thermostatically controlled; the other powered up with the gas valve.
  • RJsfishin's avatar
    RJsfishin
    Explorer
    May 04, 2015
    I wouldn't have had the fuse problem, because I wouldn't have used a fuse,.....which the fan on my fridge doesn't have a fuse.
    But I don't go shorting the positive directly to the negative either,....that's why I don't need a fuse :)

    And I don't have a switch either. If you grab your 12v source off the gas valve, you don't need no switch. It works great, except it din't fix my "F" code problem when hot sun gets on the access door.
  • yankee_camper's avatar
    yankee_camper
    Explorer
    May 03, 2015
    westend wrote:
    Well, I guess I'm confused by this:
    Well, the switch almost worked. I did turn the fan off .... after the fuse blew.

    I assumed he corrected the switch wiring but the fuse blew before he turned the fan off. Regardless, a 1 amp fuse is too small for two fans. I have computer radial fans that draw low milliamps, too. If I had two of them wired into the 12V system, I'd use a larger fuse. Lately, I wire everything with 14AWG THHN since I have miles of it.


    I did correct the switch wiring and the 1 amp fuse is still in place and never blew, but I will upgrade it as the 1 amp was recommended for just 1 fan
  • jrnymn7's avatar
    jrnymn7
    Explorer
    May 03, 2015
    Yeah, both 12v fans and pumps are way more efficient now. I use that 8" fan and a small pump for hydronic heat. Together they only draw 1.5 amps... compare that to most furnace blowers.
  • SCVJeff's avatar
    SCVJeff
    Explorer
    May 03, 2015
    If those are real fridge vent fans they pull~100ma each, so 1A should be WAY over rated. But I've popped mine before too.
  • westend's avatar
    westend
    Explorer
    May 03, 2015
    Well, I guess I'm confused by this:
    Well, the switch almost worked. I did turn the fan off .... after the fuse blew.

    I assumed he corrected the switch wiring but the fuse blew before he turned the fan off. Regardless, a 1 amp fuse is too small for two fans. I have computer radial fans that draw low milliamps, too. If I had two of them wired into the 12V system, I'd use a larger fuse. Lately, I wire everything with 14AWG THHN since I have miles of it.
  • MrWizard's avatar
    MrWizard
    Moderator
    May 03, 2015
    Most brushless pc style fans draw milliamps of current
    He said the fans ran..
    Until he put the switch across the circuit creating a short circuit when turned on
  • westend's avatar
    westend
    Explorer
    May 03, 2015
    jrnymn7 wrote:
    A 12v fan that draws 4 amps? Sounds like a wheel chock to me. I have an 8" (radiator type) fan that draws less than an amp, and several smaller ones that do likewise.
    I guess everyone has different fans, mine are old.

    The bottom line is that the OP needs a fuse on that circuit that supports the draw of two fans and 1 amp isn't enough.
  • jrnymn7's avatar
    jrnymn7
    Explorer
    May 03, 2015
    A 12v fan that draws 4 amps? Sounds like a wheel chock to me. I have an 8" (radiator type) fan that draws less than an amp, and several smaller ones that do likewise.

About Technical Issues

Having RV issues? Connect with others who have been in your shoes.24,255 PostsLatest Activity: May 24, 2025