Huge Over Amperage of Refrigerator Compressor - HELP!

[Temerity Too]

Last week I changed out my refrigerator system from a Grunert 120v, water cooled system to a Cool Blue system with a separate unit for each of the freezer and refrigerator.

We reused the Grunert holding plates (one in the fridge, and two in the freezer). The system is wired with 8ga for the 10 ft run (20 feet round trip). The refrigerator tech flushed out the plates from the R134a within the Cool Blue systems, then refilled the lost refrigerant into the systems.

The systems both cooled down as expected overnight reaching 10-15f in the freezer, and 34f in the refrigerator. Now, here's the problem - each system was drawing 10-12 amps for a total 20-24 amps! In discussions with Rich (the owner of Cool Blue) he said it was a overcharge situation, which made sense. We took the systems down to a vapor charge and then refilled with 24oz of refrigerant as indicated by Cool Blue. The systems (yes, both of them) each still drew 8-12 amps after reaching steady state (ie: normal cycling).

I then ran a 10ga wire (with the proper crimped fittings at each end) directly from the battery to each of the systems and got the same amperage draw. I measured the duty cycle for the freezer at 4/hr on and 6/hr off - so about 40%.

The systems are mounted in the engine room (about 100 cubic feet in size). The ambient air temp is about 85. With a cold engine, and the refrigeration systems running, the temp in the engine is now 130 degrees. (The temperature on sealed domes of the compressors is 165 and 170 as I write this).

Rich and I then surmised it could be that there was air/moisture/contamination in the systems. So, the frig tech vacuumed down the two systems to -30psi, and refilled again with 24oz of refrigerant. Still drawing 8-12 amps each.

Last night, with both systems at temperature and in normal duty cycle I measured the amp/hrs consumed from 9pm to 9 am, only opening the fridge once, and not opening the freezer at all. The amp/hrs consumed was 119.2, or about 240 amp/hrs per day! And, the temps in the engine room and on the compressor domes are still off the charts.

At this point, I'm out of ideas, and short of sending the units back, I don't know how to resolve this.

Any and all thoughts from knowledgeable people are greatly appreciated.

[Richard Kollmann]

Originally Posted by Temerity Too

Last week I changed out my refrigerator system from a Grunert 120v, water cooled system to a Cool Blue system with a separate unit for each of the freezer and refrigerator.

We reused the Grunert holding plates (one in the fridge, and two in the freezer). The system is wired with 8ga for the 10 ft run (20 feet round trip). The refrigerator tech flushed out the plates from the R134a within the Cool Blue systems, then refilled the lost refrigerant into the systems.

The systems both cooled down as expected overnight reaching 10-15f in the freezer, and 34f in the refrigerator. Now, here's the problem - each system was drawing 10-12 amps for a total 20-24 amps! In discussions with Rich (the owner of Cool Blue) he said it was a overcharge situation, which made sense. We took the systems down to a vapor charge and then refilled with 24oz of refrigerant as indicated by Cool Blue. The systems (yes, both of them) each still drew 8-12 amps after reaching steady state (ie: normal cycling).

I then ran a 10ga wire (with the proper crimped fittings at each end) directly from the battery to each of the systems and got the same amperage draw. I measured the duty cycle for the freezer at 4/hr on and 6/hr off - so about 40%.

The systems are mounted in the engine room (about 100 cubic feet in size). The ambient air temp is about 85. With a cold engine, and the refrigeration systems running, the temp in the engine is now 130 degrees. (The temperature on sealed domes of the compressors is 165 and 170 as I write this).

Rich and I then surmised it could be that there was air/moisture/contamination in the systems. So, the frig tech vacuumed down the two systems to -30psi, and refilled again with 24oz of refrigerant. Still drawing 8-12 amps each.

Last night, with both systems at temperature and in normal duty cycle I measured the amp/hrs consumed from 9pm to 9 am, only opening the fridge once, and not opening the freezer at all. The amp/hrs consumed was 119.2, or about 240 amp/hrs per day! And, the temps in the engine room and on the compressor domes are still off the charts.

At this point, I'm out of ideas, and short of sending the units back, I don't know how to resolve this.

Any and all thoughts from knowledgeable people are greatly appreciated.

The high amperages and compressor temperatures you are reporting far exceed the normal Cool Blue system limits and in extended operation can cause oil failure contamination.

I would guess the Grunert holding plate interior ½ inch OD evaporator coils were designed for a much larger 120 volt condensing unit. Oversize evaporator coils generally are not recommended as over time the very small compressor’s refrigerant flow velocity will trap oil and eventually cause problems. What brand compressor and size is installed in the Cool Blue units? Are you using the TXV valves recommended to limit the maximum orifice opening limiting btu flow to compressor manufactures specifications? It is also important as to where and how the TXV temperature sense tube is attached.

This is one of those catch 22 problems if you reduce volume of flow to lower compressor load you risk the chances if starving compressor of lubricating oil.