Keep blowing fuses ?

[yankee_camper]

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?

[Gene_Ginny]

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]

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]

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]

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]

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]

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]

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]

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]

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]

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.

[MrWizard]

it only works ONE WAY

it only goes in ONE WAY

you break the positive B plus line..the switch goes in just like a fuse

positive IN to switch, and positive out to the fans

[westend]

A 1 amp fuse is too little, you need a larger fuse in that circuit. Most 12V fans draw about 4 amps. The fuse should be sized to the wire used but a 5-10 amp fuse is definitely going to work better than a 1 amp fuse.

[Gene_Ginny]

Well, the switch almost worked. I did turn the fan off .... after the fuse blew. 😉

[yankee_camper]

Thanks to everyone for your help and not beating up the dummy (me), this site has helped me tremendously in the past and I'm sure in the future. Thanks All!