Helium..........non-flammable
Hydrogen.....FLAMMABLE
Other than that........not much difference
Ford's RV Training & Service tested an Atwood Helium & Dometic Hydrogen RV Fridges.
Conclusion:
The bottom line is that the helium absorption refrigerator provides adequate refrigeration and performs well relative to the hydrogen absorption refrigerator. One concern that should be noted is the inability of the Atwood models to restart operation after a power outageFord's RV Training & Testing.........
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