Switch for cooling fans

[MRF]

Hello All:

I just joined the Good Sam Club and RV.NET. This is my first post.

This is also my 1st RV experience. I bought a used RV from my friend and am getting a considerable education, rather quickly. I have been hit with some mechanical and electrical surprises and even a refrigerator fire, at the RV service center during a de-winterization service (and yes, we are still friends). I can't wait to use this thing!

My electrical components are sitting directly below my refrigerator. I sealed all the necessary areas and installed vents with 120 mm computer cooling fans to force cool air across my electronics and up across the back of my refrigerator area, then exhausted through my roof vent with another fan. My power source is the 12 V refrigerator wiring. For right now I do not have a thermal switch, just a SPST, 2 terminal, On, Off toggle.

I am an electrical neophyte and don't want to take any chances in the RV electrical arena, of which I have no experience. You would think wiring a simple toggle is a simple task, however I have read numerous blogs and posts, some saying connect both wires to the back of the toggle, some saying place the power wire on the toggle and run the other one to an independent ground and one with no mention of ground at all.
Which is correct????? That is the 1st question.
2nd question: Do you think I should put in an in-line fuse?
Any input would be greatly appreciated.
Thank you
MRF

[MRF]

Ozlander wrote:

Chris Bryant wrote:

MRF wrote:

My electrical components are sitting directly below my refrigerator. I sealed all the necessary areas and installed vents with 120 mm computer cooling fans to force cool air across my electronics and up across the back of my refrigerator area, then exhausted through my roof vent with another fan.

I may be misunderstanding this statement, but it sounds like you have opened up vents between the bottom of the refrigerator and electronics beneath it. This is a very bad idea- the base the refrigerator is sitting on must be sealed and vented out the side- assuming we are dealing with a standard gas/electric model. LP gas is heavier than air.

That is true. In case of a propane leak, you'd want the gas to vent to the outside, not the inside.

I just updated with some clarifying info. I think I am OK for now.
BTW, an RV dealer and service center capped my gas line and I had it checked for leaks.

[MRF]

Chris Bryant wrote:

MRF wrote:

My electrical components are sitting directly below my refrigerator. I sealed all the necessary areas and installed vents with 120 mm computer cooling fans to force cool air across my electronics and up across the back of my refrigerator area, then exhausted through my roof vent with another fan.

I may be misunderstanding this statement, but it sounds like you have opened up vents between the bottom of the refrigerator and electronics beneath it. This is a very bad idea- the base the refrigerator is sitting on must be sealed and vented out the side- assuming we are dealing with a standard gas/electric model. LP gas is heavier than air.

Good catch!............THANK YOU FOR THAT INPUT!
I did not think of that. It is only blind luck that I am safe with my present set up.

You are correct in the venting, but I failed to clarify; I am temporarily using an apartment size, electric only fridge. Once this new RV experience/experiment is underway and if it becomes a regular part of my lifestyle, I will remove a couple of my modifications and pony up the $$$$$$ (ouch) for an RV fridge and install it properly, to include a correctly sealed and vented area. Everything I have done is easily reversible or alterable to accommodate an RV technology fridge. I already have a second cut and sized drop in floor. I will reposition the bottom fan for the electrical only (5 min), redirect the middle fan (5min) to cool the refrigerator rear area, only and leave the roof fan as is.
I am still licking my financial wounds from $6000 worth of surprise expenses in an RV I haven't even used yet, so I didn't rush to pay $1500 to $2000 for a new Norcold or Dometic.
(Insurance would only pay for the resultant fire damage, but NOT the fire source, which was the refrigerator. I am in the process of trying to get the cost covered through the insurance company's subrogation with Norcold.)

[Ozlander]

Chris Bryant wrote:

MRF wrote:

My electrical components are sitting directly below my refrigerator. I sealed all the necessary areas and installed vents with 120 mm computer cooling fans to force cool air across my electronics and up across the back of my refrigerator area, then exhausted through my roof vent with another fan.

I may be misunderstanding this statement, but it sounds like you have opened up vents between the bottom of the refrigerator and electronics beneath it. This is a very bad idea- the base the refrigerator is sitting on must be sealed and vented out the side- assuming we are dealing with a standard gas/electric model. LP gas is heavier than air.

That is true. In case of a propane leak, you'd want the gas to vent to the outside, not the inside.

[MRF]

tenbear wrote:
If you are adding new wire to reach the switch position, use the same size wire that is currently used. If you use smaller wire you will need a smaller fuse. It is probably wired with # 14 wire if it has a 15 amp fuse.

Thanks to tenbear, good advice.

[Chris_Bryant]

MRF wrote:

My electrical components are sitting directly below my refrigerator. I sealed all the necessary areas and installed vents with 120 mm computer cooling fans to force cool air across my electronics and up across the back of my refrigerator area, then exhausted through my roof vent with another fan.

I may be misunderstanding this statement, but it sounds like you have opened up vents between the bottom of the refrigerator and electronics beneath it. This is a very bad idea- the base the refrigerator is sitting on must be sealed and vented out the side- assuming we are dealing with a standard gas/electric model. LP gas is heavier than air.

[tenbear]

If you are adding new wire to reach the switch position, use the same size wire that is currently used. If you use smaller wire you will need a smaller fuse. It is probably wired with # 14 wire if it has a 15 amp fuse.

[MRF]

For Mexicowanderer:
Interesting idea and will consider it. Thank you

[MRF]

10-4 to CA Traveler.... will do........Thank you

[MRF]

For Harvey51
Thank you very much. I will take care of that tomorrow. I was a little gun shy, because the certified electrician I had (non RV experienced) already had wired something backwards and I was almost facing a second fire. Scary, huh?
Feeling much better now.
Thanks again.

[CA_Traveler]

Harvey51 wrote:
Electricity goes around in a circuit, starting at the battery, going through the load and back to the battery. So you want to run it through the switch or thermostat so it can interrupt the flow. Just one wire will go through the switch, not two. The positive wire should be switched. Positive to the switch, then from the wire on the other side of the switch to the fan positive, then from its other wire back to the battery either through a ground or negative wire in the fridge.

Make sure there is a fuse on the positive wire. An existing circuit should already be fused and adequate to add the fan loads. Otherwise add a new fuse near the battery.

[Harvey51]

Electricity goes around in a circuit, starting at the battery, going through the load and back to the battery. So you want to run it through the switch or thermostat so it can interrupt the flow. Just one wire will go through the switch, not two. The positive wire should be switched. Positive to the switch, then from the wire on the other side of the switch to the fan positive, then from its other wire back to the battery either through a ground or negative wire in the fridge.

[MEXICOWANDERER]

Go to the hardware store.

Ask for a MECHANICAL DIAL TYPE wall thermostat for a HOME AIR CONDITONER

This is a high amperage thermostat for AIR CONDITIONING. It has four wires sticking out of it.

The four wires are TWO PAIRS, meaning in 300 years when one side wears out, connect the other pair. There are clear diagrams.

Screw the thermostat to the inside ROOF of the compartment. Spin the dial on the thermostat until which temperature you want the fans to come on at. The dial has painted numbers in Fahrenheit on it. Hard to go wrong. Adjust to your taste in temperature.

From then on, it's all automatic. When it gets hot the fans come on.

Slam the compartment door and forget about switches. The thermostat dial when turned all the way down clicks the whole shebang off just like a switch.

The wiring of this thing is so simple it is hard to believe. Just connect with butt connectors.

Rated for 25 amps DC. It'll do the job and there ain't no steenking batteries.

Turn off the electrical system (batteries) for the winter or when storing for long periods of time.

[1492]

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