Electrical Work Safety?

[Rounder44]

Hi,

I'm about to change the thermostat on a 2019 Sport 22FB with solar factory package.

Got me to thinking about how to turn off the power!

I assume but want confirmation that to proceed safely I need to be unplugged from shore power AND have battery switch to off...right?

Or should I un hook the battery completely?

Or....?

All I need for now is to make sure I can remove and install the thermostat properly. I bought a Honeywell 12v digital furnace only model. Runs on 12v or AA batteries. A model I've read others installed with no issues.

Thanks,

Rounder44

[mayco]

From the web...

These are some general guidelines when working with electricity on vehicles:

Always remove any jewelry, to include rings, necklaces, watches, etc. If one of these items should come in contact between a hot and ground, it will instantly go hot (if there's enough amperage flow) and will burn into your skin requiring surgery to remove. These are a "no matter what" situation. There are also some physical reasons for removing these items as well.
Disconnect the battery whenever working on anything which is voltage sensitive, such as the Engine Control Unit (ECU - vehicle's computer). This especially applies when working on the airbag system (SRS), though other precautions need to be taken there as well.
Disconnect the battery whenever working on parts which need high amperage to operate, like the starter and alternator. These are items which, if the main power were grounded, would cause large issues for you and your vehicle. (Think thermonuclear meltdown.)
Generally no need to disconnect the battery when changing out anything which involves low current or anything which is switched. That means it has no live wires going to it when switched off. This includes doors, light bulbs, etc.

[rmkrum]

Mayco obviously has been there, and done that...

My personal preference is to always disconnect the negative lead from the batteries, and tape it down far away from the batteries. Gives me a warm fuzzy feeling that it won't reach out and bite me somehow. Dittos with shore power cable--if I unplug it at BOTH ends, it's not likely to bite me. Remember that you are working in and around a conductive tin can, and it only takes one slip to get zapped.

Had a very close call one time, working on some 480 volt water pumps. Pulled the main disconnect for the 440 panel, and was disconnecting some pilot circuits connected to the panel. Turned out the pilot circuit was powered and breakered somewhere else--in a 115 volt panel all the way across the factory floor, and it was NOT marked (yet).

I pulled off a wire nut, and the wires jumped apart, one hit the conduit, sparked like hell, and popped the breaker for me. Good thing I always assume it's hot until proven not, and was working one-handed. Scared the you-know-what out of me and the safety observer, since we were both standing on a wet concrete floor at the time. Now I use a proximity voltage detector before I touch anything to make SURE the circuit is dead. Cheap insurance, because slow electrical cooking is a lousy way to die...

[Mattirs]

Originally Posted by mayco

From the web...

These are some general guidelines when working with electricity on vehicles:

Always remove any jewelry, to include rings, necklaces, watches, etc. If one of these items should come in contact between a hot and ground, it will instantly go hot (if there's enough amperage flow) and will burn into your skin requiring surgery to remove. These are a "no matter what" situation. There are also some physical reasons for removing these items as well.
Disconnect the battery whenever working on anything which is voltage sensitive, such as the Engine Control Unit (ECU - vehicle's computer). This especially applies when working on the airbag system (SRS), though other precautions need to be taken there as well.
Disconnect the battery whenever working on parts which need high amperage to operate, like the starter and alternator. These are items which, if the main power were grounded, would cause large issues for you and your vehicle. (Think thermonuclear meltdown.)
Generally no need to disconnect the battery when changing out anything which involves low current or anything which is switched. That means it has no live wires going to it when switched off. This includes doors, light bulbs, etc.

When working on something you turned off with a switch, put a big piece of tape over the switch saying, "Do not throw this switch!" Hopefully they will ask why before taking the tape off and throwing the switch.

If they do scream real loud, fall to the floor, flop a couple of times and then don't move.[emoji48]

[overlander63]

I'm pretty sure that furnace has an onboard switch. To access, remove the outer cover, reach in, and turn the swith "off".
When you're done, turn the switch "on", and use the furnace.
If you don't want to do all that, locate the furnace fuse in the 12v fuse panel, and remove it.
No need to overcomplicate things.

[SilverHouseDreams]

I unplugged from shore power and put my battery into store mode before changing to the same thermostat. If the furnace can’t turn on, because of store mode, then the voltage to the thermostat is absent.

I also have a piece of electrical tape I use to cover the negative or one of the AAA batteries when storing the trailer so that the batteries don’t go dead for no reason.

[uncle_bob]

Hi

If this stuff really freaks you out - have somebody else do it for you. Having a heart attack while worrying about this or that is at least as likely to kill you as something in a 12V circuit. I'm by no means suggesting that safety is a bad idea, only that there are indeed other issues as well.

Bob