Refrigerator ??

[JoLin]

I would expect marine fridges to adhere to the SAE marine standard for spark protection, like marine starters and alternators.

That's the question, and I can't find anything to support that opinion. I've had a few days to think about this, and here's my take...

1. NO QUESTION that anything residing in the bilge, or in an area where explosive vapors are likely to collect, must be intrinsically safe (spark protected). That includes engine ignition and electrical components, inverters, water heaters, etc., all of which are built to that 'marine' standard. I would not (and never have) use anything else.

2. The alcohol/electric cooktop in my cabin is an Origo marine unit that's in wide use on boats. The electric components are the same as you'd see in any other electric cooktop. Source wires plug into the rheostat and resistance coils using simple spade connectors. There's no vapor proofing or spark protection. The danger of using the alcohol burners is obvious, but I and thousands of others use them in both modes without incident.

3. My air conditioner was manufactured by Flagship Marine, which is also a major supplier to the USCG. No sealed circuit boards or other electrical components. Relays, transformer, capacitor, etc. are all off the shelf parts packed into a metal box and connected up with butt, ring and spade connectors. Not vapor proof or spark proof. The one electrical component that resides below the cabin sole and water line, is an intrinsically safe, marine-rated March circulating pump.

4. The 120-volt side of my Dometic marine refrigerator is fed by a power cord with a 3-prong plug, plugged into a wall receptacle, like the ones in your house. If you've ever removed an OE 'marine' microwave oven from a boat, they're connected the same way. They're also the same units used in RV's. I contend that the term 'marine rated' for these appliances refers to corrosion resistance and shock (as in g-force) protection.

5. Boaters (including most of you here) routinely use household microwave ovens, coffee makers, blenders, circulating fans and heaters (both electric and propane) in their cabins. Most of 'em came from WalMart

If I've missed something, please point it out. It's an important subject that we can all learn from.

 

[frantically relaxing]

There's nothing magical about marine fridges except the $600 upcharge for a Danfoss compressor that'll run off 12 volts. No spark protection is needed since as was pointed out, it's not in the bilge. Boats have microwaves, TV's, VCR's, coffee pots and lots of other heat or spark sources that have no 'marine' requirement. And most small fridges use around 75 watts of power. I found a $144 1.6 cu.ft.SPT 'home' fridge that eats 1.1 amps @ 120v, and a $675 1.75 cu.ft. Isotherm 'marine' fridge that eats 2.5 amps at 120v. No matter how you slice or dice it, the marine fridge takes more than twice the power to run! So whether you're using an inverter - which uses power itself remember- to run the SPT or straight batteries to run the Isotherm, the SPT is going to use a lot less power!

This is just one example- I found a 2.5 cu.ft marine fridge that only consumes 3/4 amp @ 120v, and you can find small home fridges that eat 5 amps or more. So if you have an efficient inverter, and do your homework, there's no reason a 'home' fridge won't work on your boat...