March, 1928] 



Electric Dairy Cold Storage 



17 



The rokl storage tompcraturo was 44°. The temperature of the air 

 going to the cooling coils of the comi)ressor was 74" and tliat leaving 

 it was 84°. 



The high cold room temperature reading shown in the table gener- 

 ally occurcd just after defrosting and di'oppcd ([uickly as soon as the 

 current was again turned on. 



To obtain some idea of the effect of tlie uninsulated concrete floor, 

 the soil just adjoining (one foot away from floor) was tested and found 

 to be 60° four inches below the top of the bricks and 58° eight inches 

 below tlie surface. Eight feet away from the room similar test show- 

 ed 62° and 60°. This indicates the continual warfare between the 

 machine and the floor — one attempting to hold the storage at 44° and 

 the other presenting an op])osing temperature of about 60°. Inasmuch 

 as the coldest air in the storage falls to the floor, this is the most im- 

 portant surface to j^roperly insulate. A concrete floor has no insulat- 

 ing qualities alone and transmits moisture very rapidly. These dif- 

 ficulties can be overcome by insulating underneath the concrete. The 

 best practice is to double the amount of insulation that is required in 

 the wall surfaces. 



Time of Operation of Machine. Due to the system of automatic con- 

 trol, tlie times of day that machines operate were not obtained; but 

 observation indicates that it is largely daylight operation on all three 

 farms. 



The percent of the total time that the motor equipment has operated 



Fig. 6. The motor driven mechanical 

 unit that i.s located outside of the 

 room and connected to the brine tank 

 which is placed inside the storage. 

 The same style unit is used on the 

 three farms. 



