bdosborn wrote:Front opening door very attractive compared to the lift up lid that is pretty standard on car fridges, but every time you open the door all the cold air falls out and the fridge must chill a fresh batch of ambient air.
Air doesn't hold much heat, its a great insulator so opening the door doesn't really affect battery usage. I tested mine by pulling a beer out every 1/2 hour or so and it didn't affect the energy usage at all.
Not meant for being used while moving, and you certainly will struggle to find any sort of recommendation regarding what angle the fridge can operate at.
The big RV crowd is replacing their failing absorption fridges with full size AC units. Dometic had a bad batch and ammonia leaks were causing fires. I haven't seen any posts bout premature fridge failures for the AC type but maybe I ought to do some more checking.
I want a bigger fridge, and the DC units are in the $800-$1,000 dollar range. I can get the same size AC unit for $180. So I could break a few and still be ahead.
Bruce
While you are certainly correct in saying air doesn't hold much heat it does hold some.
Which is why, when you use air as an insulator, you have to make sure it can't move.
More than one fridge operating manual I have read lately recommends closing the lid gently so as to avoid displacing the cold air with hot thereby causing the compressor to run unnecessarily.
here in Oz, you could taking that cold beer out in 45C heat, and trust me the compressor will kick in.
And yes, you can certainly be ahead money-wise buying an AC unit, but bear in mind a big RV probably won't knock a fridge around as much as a teardrop would.
But anyway, it is up to you. Get one, set it up and report back. I'm keen to know how much inverter losses you see, and how big the inverter has to be for staring current.
OP827 wrote:Do 12VDC compressors use brushless motors that suppose to be more efficient in comparison to 120VAC compressors that use induction motors or it is not the case?
They use all sorts.
The Engel fridge doesn't use a rotating motor at all - it has a piston that is pulled back and forth by magnetic fields.
Run by a built in inverter it seems, so likely to be not as efficient as suggested.
Danfoss/Secop compressors seem to be rotating motors with a crank driven piston, again operated by a "control module" that is called an inverter when ordering spares.