Ammonia Fridges, read an interesting piece a while ago

Our Norcold was suddenly having a problem staying cool in 100+ sunny heat. Discovered the cooling fans were not working. DH installed a fan in lower outside compartment blowing up.( Hard to get to the factory ones) We were able to put awning out ( wind calmed down) and it was back to keep the frig around 34-35 degrees. So - the frig cooling capacity can be affected by things other than the cooling unit.