The precooler in San Bernardino was used to precool LOADED reefers. I’ve talked to former precooler staff and they stated enptyreefers very, very rarely were precooled and this was done “off the books” because there was a charge for the service. The only reason this was done was for cars that were pre-iced (another charge) on extremely hot days precooling the interior lessened meltage so the car receiver would get more of the ice they paid for.
Very wrong. Fruit Growers Express put mechanical reefers into service in 1949. Santa Fe (SFRD) and PFE did so in 1953.
In 1973 the ICC permitted discontinuance of bunker icing for refrigerator cars. The railroads no longer were required to re-ice reefers in transit on their lines. This meant that large reefer fleet operators such as PFE and Santa Fe no longer could rely on other railroads to re-ice interchanged reefers.
Top-iced service (placing ice over the load) was offered after that date by some railroads that discontinued bunker icing. This service was used mainly for vegetables. Some of the ice bunker cars also continued to be used as insulated boxcars but the number of ice bunker reefers in revenue service declined rapidly after 1973.
“The produce packing houses in Redlands California and other nearby towns didn’t have their own ice house.”
Actually, a number of packing houses did have their own icing facilities because ice was an expensive commodity to buy from the railroad. See Jim Lancaster’s website: Packing Houses and Other Structures in Southern California (coastdaylight.com)
We have other threads with extensive coverage of various kinds of icing operation.
If it ‘paid’ a particular facility or dock to have a ‘double deck’ facilitating icing, they would build one – and I have seen pictures of them. Whether or not the mechanical ice making plant was located on that elevated deck or used some sort of conveyor or elevator would, again, be a matter of perceived economics.
There is also evidence of ‘outsourced’ ice service capable of reaching both ‘ice decks’ and individual car hatches (including the scissorlift bodies similar to equipment used for residential coal delivery that NHTX mentioned in 2018). I would expect to see more ‘specialty outsourcing’ in the waning years of iced vs. mechanical reefers, but as I don’t know, I won’t comment further than that.
While we are on this general topic, were any mechanical reefer designs that used axle generation like passenger cars successful vs. designs with Enginators or self-contained engine-driven refrigeration?
Jeff Wilson has authored two excellent books about milk and produce handling. One thing I learned was that milk tank cars did not require cooling. The tanks were so well insulated that one example he gave indicated that in 100 hours, the temperature of the milk had only risen 2 degrees. Milk that was transported in cans would often be put in baggage/express cars and top iced to keep them cool in transport.
As for produce, the requirements varied greatly depending on the commodity, location, time of year, temperatures, etc. This would dictate how often icing was needed before mechanical refrigeration became an option. In some cases, heaters would have to be placed in the ice bunkers to keep the produce from getting too cold.