Sub-Zero Error Codes Explained.
Error codes are vague, they give you an idea of what's wrong and where to look, there are hundreds across the different models and you can really go in-depth with the diagnostic mode, but you don't have time for that.
Vacuum Condenser Error
Around the late 1990s sub-zero came out with the 600 series unit. It had one or two general error codes. One of which, most common, was the "Vacuum Condenser" error code, or a general "service" error code. As the years progressed the error codes got more specific and detailed. The machines even began storing historical temperature data. It can get quite complicated but in general, the error codes can give a good idea of what is wrong with your machine or what to check for. At best, error codes act as a starting point for a proper diagnosis.
Vacuum Condenser:
This general error code would flash on 600 series units from 1998 to 2002. The idea was that the control board would log the run times of the compressors, if they ran too long or inefficiently the control board would flash " Vacuum Condenser." This is the most general of error codes there is because a machine can run inefficiently for literally any reason. Your first course of action is to vacuum your condenser. Sometimes this will work the condenser dust is making the machine run inefficient (i would put that at less than 10 percent of the time).
If this does not solve your problem, the machine is running inefficiently for another reason, and we have seen it all.
A few reasons we commonly see units triggering this message are as follows:
- Refrigerant Leaks
- Bad Fans
- Bad Door Seals & Gaskets
- Defrost Issues & Frost Ups
- Old Compressors & Clogged Heat exchangers
- Severely Clogged Condensers with grease or bent fins.
So, at the end of the day, a vacuum condenser light is super vague and if a general Vacuuming does not help and temperature loss is happening, give your service provider a call. If you are in the New York & New Jersey area, that should be us.
Other than the Vacuum Condenser light, we would often see the "service" light illuminate on these early 600 series units. The service light on early units would usually illuminate if the board had lost proper communication with one of its thermistor sensors, or ice makers solenoid had energized too long. A simple toggling of the on/off button should reset the code. If the code comes back or you have noticed any irregularity in the ice maker system, just get a service tech over to diagnose. Otherwise, reset it and see what happens(it usually comes back)
Moving on: EC (error codes)
OK, so the Vacuum Condenser light was definitely helpful, but it's 2002 and there is new computer technology being implemented into the appliance industry, they wanted to take it a step further so they began adding "EC Codes" to machines. These error codes would give helpful hints as to what part of the fridge was malfunctioning. They implemented these codes on all of the products, 600 series, 700 series, even the Pro48 and 400 series wine coolers. The units would often flash "service" and then flash over to the "EC" code. Looking up the codes online gives you vague answers to the actual problem so I'll list some of the official error code explanations and give my opinion on what I would do.
Watch this video and learn how to enter "Diagnostic Mode"
Most sub-zero fridges after serial starting with 181 have a more comprehensive diagnostic mode.
To access it press and hold the “colder” and “unit on/off” buttons at the same time and then let go.
You will be brought into diagnostic mode.
EC 05
Refrig. Cabinet Thermistor read open or shorted for 10+ seconds, or repeatedly read erratic temp’s
What this means - The sensor that reads the air temperature in your refrigerator is either bad, has a bad connection or is getting a big range of irregular temperature readings. You may have a bad thermistor, you may have a cooling issue.
What to do- I see "evaporator" thermistors go bad more often than "cabin" thermistors. Vacuum your condenser, reset your error codes by holding the "alarm" bell button for 15 seconds. If it comes back, change your thermistor or call a service technician.
EC 06
Refrig. Evaporator Thermistor read open or shorted for 10+ seconds, or repeatedly read erratic temp’s
What this means - The sensor that reads the evaporator temperature in your refrigerator is either bad, has a bad connection or is getting a big range of irregular temperature readings. You may have a bad thermistor, you may have a cooling issue.
What to do- I see "evaporator" thermistors go bad more often than "cabin" thermistors. Vacuum your condenser, reset your error codes by holding the "alarm" bell button for 15 seconds. If it comes back, change your thermistor or call a service technician.
EC 07
Freezer Cabinet Thermistor read open or shorted for 10+ seconds, or repeatedly read erratic temp’s.
What this means - The sensor that reads the cabin temperature in your freezer is either bad, has a bad connection or is getting a big range of irregular temperature readings. You may have a bad thermistor, you may have a cooling issue.
What to do- I rarely have changed thermistors in freezers, check that the freezer is not frosting up. Vacuum your condenser, reset your error codes by holding the "alarm" bell button for 15 seconds. If it comes back, call a service technician.
EC 06
Freezer Evaporator Thermistor read open or shorted for 10+ seconds, or repeatedly read erratic temp’s.
What this means - The sensor that reads the evap temperature in your freezer is either bad, has a bad connection or is getting a big range of irregular temperature readings. You may have a bad thermistor, you may have a cooling issue.
What to do- I rarely have changed thermistors in freezers, check that the freezer is not frosting up, verify the fans are spinning when you close the door. Vacuum your condenser, reset your error codes by holding the "alarm" bell button for 15 seconds. If it comes back, call a service technician.
EC 20
Defrost Underheat with No Voltage Feedback Through Gray/White Wire at Defrost Start
What this means - Your control board is monitoring your defrost through feedback through a wire connected to your defrost system. It doesn't recognize feedback (voltage) and the heaters didn't run long enough.
What to do: Check for a frost up in your freezer, is there frost on the ceiling or back wall? Are your temperatures steady? If everything checks out and the machine is working reset the code. If you have a frost up, go ahead and shut off your freezer to fully defrost it. If the code comes back, you have something affecting your defrost system, maybe a bad harness or wire connection, maybe a bad terminator or heater. Call for service.
EC 21
"Defrost Overheat"
What this means: Your defrost heater ran too long.
What to do: Reset code. If it comes back get it addressed, if the heaters run too long it can be disastrous.
EC 24
"defrost underheat"
What this means: Your defrost heater did not run long enough or did not get hot enough.
What to do: Check for a few things, make sure you dont have an ice up on freezer evaporator, check that the evaporator fan is spinning when machine is on. Reset code, if it comes back call for service. EC24 codes can be pretty general, units can frost up for all sorts of reasons and trigger this code.
EC 30
"Excess IM Water Valve Solenoid Activation (> 15 Seconds)"
What this means: Your ice-maker solenoid was energized by your icemaker for longer than 15 seconds.
What to do: check your ice, is it irregular shaped? The ice maker bin may be overflowed with ice at this point. When your ice maker is ready for water, it will send electricity to your solenoid valve, this should last maybe 6 seconds. 15 seconds is too long and if you have a good water supply this should overflow your ice maker and its bin. Reset the code and if you see any leakage in your ice system call immediately.
EC 40
"Excessive Freezer Comp Run"
What this means: Your freezer compressor is running too long and working too hard for some reason. This is isolated to your freezer section only.
What to do: Have you cleaned your condenser? Are your fans spinning? Do you have a frost up in your freezer? Is the door shutting well, how do the gaskets look? There is a lot to digest with this code but just make sure your condenser is clean and reset the code. If it is overheating again schedule service.
EC 50
What this means: Your refrigerator compressor is running too long and working too hard for some reason. This is isolated to your refrigerator section only.
What to do: Have you cleaned your condenser? Are your fans spinning? Do you have a frost up? Is the door shutting well? Make sure your condenser is clean and reset the code. If it is overheating again schedule service to have your machine professionally evaluated.