I conducted a heat pack test trying to push the limits to the extremes to see what the temp in the box would be.
I should have took photos (sorry) but I will try to explain the best I can what I did:
I had a 8x8x6 shipping box insulated on all sides with 3/4 inch Styrofoam . The box had one very small air hole punched in only one side.
Inside the box I have a plastic pre-punched deli cup. I put a remote thermometer inside the deli cup and snapped the lid on.
I unwrapped and started TWO 40 hour heat packs and let them warm up in a towel for about 45 min. I then took the warming packs and wrapped them in newspaper and placed them on either side of the deli cup...as if I where packing a real chameleon.
Newspaper was packed in all the loose areas securing the deli cup in the middle.
I sealed up the box and let it sit inside for a two hours to simulate it sitting inside at the UPS center. Them moved outside where it was slightly cooler.
I also had a thermometer to measure outside temp.
Heat packs where started about 10:00 and put in the box at about 10:55
TIME / OUTSIDE TEMP / INSIDE BOX
11:00pm / 76 F / 78 F
3:00AM / 70 F / 88.5 F (4 hours in the box)
Moved box at 3am (yes I got up at 3 am in the name of science) to the refrigerator set on the highest settings (45 F) After 4 hours at 45 degrees I turned the temp setting of the fridge down to 32 degrees
7:00 AM / 45 F / 68 F (8 hours in the box)
8:00 AM / 41 F / 67 F (9hrs)
9:00 AM / 39 F / 64 F (10hrs)
Now I decide to push the results more and put the box in the freezer The freezer is on its highest setting which is 8 degrees. My outside thermometer started to giveme error readings that looked like "L L L" ( I will just assume that means 'freakin cold')
10:00 AM / ERROR / 51 F (11hr)
10:30 AM / ERROR / 47.5 F (11.5hr)
11:00 AM / 14 F / 42 F (12hr)
12:00 PM / 19 F / 43 F (13hr)
1:00 PM / 15 F / 40 F (14hr)
1:30 PM / 15 F / 38.7 F (14.5 hr)
I ended my experiment there but placed the box back in the fridge just to see how much longer the heat packs would heat the box. I went out to run errands and returned at 5:00 pm
5:00 PM / 39 F / 50.3 F (18 hrs)
I unpacked the box at 5:30pm after 18 hours inside the box. The heat packs seemed warm to the touch but not hot. the newspaper not in direct contact with the packs where cold.
This was the only heat pack experiment I have done and I used Two 40 hour heat packs. I found the results very interesting. It seemed to do very well when the outside temp is 40 degrees.
Also I was surprised that the temp inside the box never dipped to freezing (32 degrees) even when the outside temp was 14 degrees.
I also now know that my settings on my fridge and freezer are not accurate. Setting the temp on the freezer to 8 degrees yield a inside temp of 14 degrees and also the fridge set on 32 never got lower than 39...
I should have took photos (sorry) but I will try to explain the best I can what I did:
I had a 8x8x6 shipping box insulated on all sides with 3/4 inch Styrofoam . The box had one very small air hole punched in only one side.
Inside the box I have a plastic pre-punched deli cup. I put a remote thermometer inside the deli cup and snapped the lid on.
I unwrapped and started TWO 40 hour heat packs and let them warm up in a towel for about 45 min. I then took the warming packs and wrapped them in newspaper and placed them on either side of the deli cup...as if I where packing a real chameleon.
Newspaper was packed in all the loose areas securing the deli cup in the middle.
I sealed up the box and let it sit inside for a two hours to simulate it sitting inside at the UPS center. Them moved outside where it was slightly cooler.
I also had a thermometer to measure outside temp.
Heat packs where started about 10:00 and put in the box at about 10:55
TIME / OUTSIDE TEMP / INSIDE BOX
11:00pm / 76 F / 78 F
3:00AM / 70 F / 88.5 F (4 hours in the box)
Moved box at 3am (yes I got up at 3 am in the name of science) to the refrigerator set on the highest settings (45 F) After 4 hours at 45 degrees I turned the temp setting of the fridge down to 32 degrees
7:00 AM / 45 F / 68 F (8 hours in the box)
8:00 AM / 41 F / 67 F (9hrs)
9:00 AM / 39 F / 64 F (10hrs)
Now I decide to push the results more and put the box in the freezer The freezer is on its highest setting which is 8 degrees. My outside thermometer started to giveme error readings that looked like "L L L" ( I will just assume that means 'freakin cold')
10:00 AM / ERROR / 51 F (11hr)
10:30 AM / ERROR / 47.5 F (11.5hr)
11:00 AM / 14 F / 42 F (12hr)
12:00 PM / 19 F / 43 F (13hr)
1:00 PM / 15 F / 40 F (14hr)
1:30 PM / 15 F / 38.7 F (14.5 hr)
I ended my experiment there but placed the box back in the fridge just to see how much longer the heat packs would heat the box. I went out to run errands and returned at 5:00 pm
5:00 PM / 39 F / 50.3 F (18 hrs)
I unpacked the box at 5:30pm after 18 hours inside the box. The heat packs seemed warm to the touch but not hot. the newspaper not in direct contact with the packs where cold.
This was the only heat pack experiment I have done and I used Two 40 hour heat packs. I found the results very interesting. It seemed to do very well when the outside temp is 40 degrees.
Also I was surprised that the temp inside the box never dipped to freezing (32 degrees) even when the outside temp was 14 degrees.
I also now know that my settings on my fridge and freezer are not accurate. Setting the temp on the freezer to 8 degrees yield a inside temp of 14 degrees and also the fridge set on 32 never got lower than 39...
