Yeah. Absorption cooling uses only gravity to create the flow-- there is no pump or compressor, which consume alot of energy. There is a slope to the coils but its gradual. If you are on an incline, the flow may be impeded or actually stop, because the gravity based system can't overcome the incline.
Conventional refrigeration with a compressor (like your a/c) isn't as subject to gravity so it can work on an incline -- at least, according to most manufacturers "up to 30 degrees". Same goes for conventional compressor or AC/DC fridges we discussed ad nauseum on a thread a few days ago. Some of us were contemplating using a compressor based fridge instead of an absorption one. Not because they can operate out of level (which they can) but because they get colder.
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