Why does my reefer have to be at -10?

well here is why.

food safety.

it is a general order to keep a reefer at -10° because of the fda has looked at hundreds of reefers and found that even factory new has losses with ambient temps being average, like 70° that can cause problems with specific frozen foods, so it is easier to make a blanket “order” to lower the risk of thawing.

see reefer insulation degrades with time, one reason why buying use, it is best to get it tested which is a days worth of running and testing to see if it maintains temperature. Validation is a longer process but costly.

so if you guys are interested in details …

https://www.gcca.org/sites/default/files/Refrigerated Transportation Best Practices Guide WEB.pdf

 

Far easier and faster to just use a thermal camera to see how degraded the walls/floor/ceiling are.

 

True but to do this without understanding what you are seeing, well …

 

Speaking of thermal imaging cameras, remember when Caterpillar teased us with a cell phone that was supposedly going to have a thermal imaging camera built-in? I remember signing up to get one of those when they started production, but don't ever remember getting the email. Wonder whatever happened with that?

Edit: Just looked and apparently they are making them.

Made Mighty | Cat Phones USA

 

Having worked with refrigerated freight for many years my guess your new in this field which is fine, what happens when you pick up chilled or frozen freight from the warehouse what ever temp the product is at when it is loaded this is what it will stay at provided the reefer is also run at that set temperature.

So if they say run it at - 10 F then run it at - 10 f this will ensure that the produce stays at or near to the temperature it was loaded at. However if you do not run it at the advised temperature then the product particularly if it is frozen will start to melt and both the receivers and your company will not be happy with you if this is allowed to happen.

In fact some warehouses I've loaded out of will insist you pre- chill your reefer to a certain temp before they will even load you. While others simply ask you to bring the reefer temp down to a certain temp after it is loaded before they will allow you to leave. What makes this job harder is not all reefers are designed to chill frozen freight and have a very hard time getting down to that - 10 f temp. There great for chilled temps between 33f - 45 f no problems its when the reefer is required to go below that -0 f level that it really tests the motor out.

One secret I learned when I had to wait for my reefer to cool down to a set temp before dispatch and security would let me depart is unhook your prime mover/ tractor from the trailer this allows more air into the reefer and its surprising how cool it will get, I found this out one day while waiting for my reefer to drop its temp down it just would not go below about 0 f fortunately another driver who'd paid a fridge mechanic to fix his reefer gave me some free advice I listened and from that day forward never had the same issues with keeping frozen temps down.

 

My last truck had a digital gauge for the bunk heater. I set it at 58 degrees and it would keep the cab at 70 degrees.

One of my tenants complained to the city that her place wasn't warm enough (I pay for heat and the thermostat is in another unit). Three different thermometers (hers, mine and the city's) read three different temperatures (mine matched the thermostat, the city read a little hotter, hers was way the Frick off).

If the shipper has drivers set the reefer below what is needed then they can be reasonably certain the product will still be viable at deliver, regardless of how well maintained the equipment is.

 

They want the product frozen. Your freezer at you house is usually -10 to -20, same principle.

 

Only way to tell hot/cold spots. Not that hard to understand what you see on the image. Take an image of a new(er) trailer and transpose over the old one.