I hope I've caught Mr. Elliot's attention with the subject line.

here is a site that explores the ammonia/water heat absorption type
of refrigeration cycle, "somewhat" akin to what is used in the Westy.

Note the Smithsonian exhibit.

http://www.ggw.org/~cac/IcyBall/crosley_icyball.html

Alistair

'82 westy, diesel converted to gas in '94
http://www.members.shaw.ca/albell/