Unit pulls 30 amps. for 3 sec. then shuts out. 15 minutes later unit will run and satisfy.t-stat seems to work. wires are not crossed/bare. coils are clean. r-404 unit. not much experience with these semi-hermetic compressors. thanks Carrier freezer CMCT-6-4 ser 1870197

Hello;

My name is Peter. I am a retired field service refrigeration technician.

How do you know you fully defrosted the freezer? You have a defrost timer and heater to do that. Unplugging your unit for a few hours may not be enough.

You need to remove the lower back wall cover. There are several screws holding it on and the rubber molding around it easily pulls out.

Up plug your unit and remove the lower back cover.

1.) Frozen Drain - Your unit goes through a defrost cycle every 8-10 hours. During the time your freezer shuts down for 20-30 minutes except for your light. If you have a frozen drain, the condensate builds up behind the lower back wall until the cooling(evaporator) coils become plugged up and you do not get any air flow. You may even have a solid block of ice.
Repair: Using a hair dryer (DO NOT Use Metal Objects. You may damage the coils.) slowly defrost the coils. This will take 2-3 hours.

2.) Cooling (Evaporator) Fan Failure - Assume the coils are not iced up. Is your evaporator fan running?



Part #: 3-60336-001 Cost: $115.00
Check it out: With a multi-meter set to the lowest Ohms (Omega Symbol). Is the motor humming, Then it is bad and needs to get replaced.
Unplug the unit. Disconnect the motor. Put one meter lead in one connector socket and the other lead in the other motor sock. You should get a reading of "0" Ohms if the motor is good. Anything else the motor is bad and need to be replaced.

3.) Defrost Timer - Pull your unit out to access the lower back. With your unit plugged in, take a small flat head screw driver, insert it into the slot on the time. Turning clockwise one turn at a time, until the freezer shuts off. If you have turned one full cycle, then you have a bad timer.
Ok. The unit shut down except for the light. Observe the metal bar below your cooling coil. Is it hot? If not then you may have a bad defrost heater. Lets check it out - Unplug your unit. Once again with your multi-meter set on the lowest Ohms, disconnect each ends of the wire connectors. Be careful not to touch the fins on the cooling coil. They are razor sharp. The connector are hard to pull apart. Put one meter lead in one connector and the other meter lead into the other connector. If you do not get a Ohm reading between 50-250, then you have a bad defrost heater.

Substitution: 3-80405-003 Cost: $56.00
This is a glass tube with a spring in it. If it is burner or the spring is broken then you have a bad defrost heater.

4.) Refrigerant Leak or Obstruction - With the unit plugged in. Lay the lover cover the cooling coils. Close the door and wait 30 minutes. Remove the cover. Do all of the coils have a nice frost pattern? Is there a block of ice in the upper right hand corner of the cooling coil. If so you either have a refrigerant leak or an obstruction. In this case the repair will cost you $450.00-$500.00.

5.) If all of the above is good, then you may have a Bi-mel problem. In the upper right hand corner of your cooling coil there is a thermostat. This controls the temperature and compressor start-up. This may explode in the back. Check to see if it is intacted.

5.) Bad thermostat - These can not be checked for failure. If you have check all of the above this may be your problem.
Substitution: 4-83053-003 Cost: $68.00

Hello;

My name is peter. I am a retired field service refrigeration technician.

"Of" means you are locked into the defrost mode. This is where your unit will shut down every 8-10 hours. Everything will stop running except for the light. The defrost mode take about 20-30 minutes where the heater turns on and defrost the cooling coil, then the unit turns back on.

Some upright freezer have a separate defrost timer, but not yours.

Your defrost timer is built into your control board.

PART NUMBER: 297366300 - Cost: $70.00
If you go into the internet you may be able to get the board for $40.00.

Install:
1.) Unplug your unit.
2.) Ground your self by touching bare metal. Static electricity will knock out a board.
3.) With a small flat head screw driver, wedge the outer frame and pop the assembly out. You only have one connector to disconnect. You may need the small screw driver to free the connector.

My name s Peter. I am a retired field service technician.
1.) First, lets check your defrost timer. You will need a small flat head screw driver. Pull your freezer out to where you can get behind it. Do not unplug your freezer yet. There is a small white box almost 2" square. On this box is a small shaft with a slot in it. Turn this dial with your screw driver slowly until your unit shuts down (Compressor not running). What you have just done is force your unit into the defrost mode.
If the unit does not shut down you have a bad defrost timer. We are not done with the defrost timer yet.
Take a break, grab a cup of coffee, allow the unit 30 minutes to defrost.
Upon returning if the freezer has defrosted you have a bad defrost timer. Unplug the freezer and replace. Easy job.
2.) Ok, not the timer. Lets check the freezer drain. At times the freezer drain freezes up. When the unit goes into defrost the condensate can not go down the drain and you build up a wall of ice behind the bottom back wall.
Unplug the freezer. Pop the setting control knob off on the lower back panel. You may need a screw driver to wedge it off. Pull the seal strips out on the 2 sides. Unscrew all of the fasteners on the back panel cover. You can not remove the cover yet. You must disconnect the temperature control. There are different mountings. Perhaps 2 screws holding the control to the back cover or a connector where you need a small screw driver to wedge them apart.
Ok, you observe a wall of ice and have a frozen drain. Do not let the freezer defrost itself, you will have a flood. Using a hair dryer and a plastic spatula melt the ice and remove it in chunks. This is a long consuming task, take you time. Be careful not to touch any of the unit components. Let the hair dryer do the work on the evaporator coil etc. Clear the drain with hot water soak up as much as you can. We do not want this to happen again - lets make a heat sink. Taking a piece of 12-14 gauge wire about 3' long, strip about 2" off one end. You should wear gloves. The fins on the evaporator coil are razor sharp. Wrap the striped end of the wire around the defrost heater (Long black bar beneath the evaporator coil). Secure it tightly. Extend the other end of the wire to your drain hole. You want to cut the wire where you strip 2" of exposed bare wire into the drain hole. So, when your defrost heater is on any ice in the drain hole will be melted. Reassemble the back panel. Plug the unit in.
I can not finish. I am limited to size of response

This is normal if your freezer is in good working condition. If your compressor runs constantly then there is a problem. Once the unit reaches the set temperature the compressor shuts down. The set temperature should be between -2 & +2 degree F. The set temperature also depends on how full the freezer is. There will be a time when the freezer like refrigerators will shut down. This is relative to the term, "Frost Free". The unit will shut down for about 10 minutes. This occurs ever 8-10 hours. The heater turns on to defrost your freezer coil. It sounds like you are in good shape.

that sounds like the hardstart relay that energizes the start windings in the compressor . if that or more likely the capacitor fails when it is first energized the compressor will pull excessive amps and cause the overload protector to open until it cools for a minute or two.

Hello;

My name is Peter. I am a retired field service refrigeration technician.

I am going to assume your compressor and condenser fan is running. Your condenser fan is in the lower back of your freezer.

You will need to remove the back cover in your freezer. There are 6 screws holding it on.

Check the following (Cover Removed):

1.) Frozen Drain - Your freezer goes into a defrost mode every 8-10 hours, where your freezer shuts down except for the lights, and your defrost heater turns on for about 20-30 minutes to defrost your cooling coil. If you have a frozen drain, the condensate builds up behind the back wall and icing the cooling coil, restricting air flow. You must defrost the coil.

2.) Freezer Fan Motor Failure - Having removed the back wall observe if the freezer fan motor is running. If not replace.

3.) Refrigerant Restriction or Leak - If you observe a large build-up of ice in the upper right hand corner, then you have a restriction or leak. The cost of repair would be about $400.00

4.) Bad Thermostat - In the upper right hand corner of you cooling coil, attached is your thermostat. They can explode, where the back of the thermostat will raise up.


You can also check it with a multi-meter, set to the lowest Ohms (Omega Symbol). You need to cut the wires, leaving enough wire length to rewire back in. Put the thermostat in a glass of ice water for 10 minutes. After, it should Ohm out around 16. It is reads '0' or infinity it is bad. Below 15 or 16 it is bad

Hi,

Many times a freezer and/or refrigerator do not work right because of a dirty condenser coil...there are also many other things that can go wrong.

If you are hearing a clicking or buzzing then check out the last two tips.

If your refrigerator is running but warm, then...

Check out these tips that I wrote about that... it is a great place to start trouble shooting your unit...and something that you can do rather then calling a repair person to do a simple thing for you...

Refrigerator Condenser Coil Cleaning Refrigerator Repair

Refrigerator Troubleshooting Refrigerator Compressor

Refrigerator Compressor Start Capacitor and Start Relay

Refrigerator or Freezer not Cooling or Getting Cold

heatman101

Hi there, just happened to see you as I was signing off. I am a refrigeration contractor, so this is something I would do. Mainly commercial units, same concept but different controls is all. Anyway, I will have to ask you questions as we go that you can get back to me on, with my user name. So, how old or new is the unit and when did you notice when this problem started?? We know that the compressor is working, but how good. It comes on and runs, but does it freeze at all before it starts to warm up? Once the compressor comes on when the cold control/thermostat calls for cooling, it should run until it reaches the desired temperature and the compressor will cycle off. Once it has frozen everything and shuts down, it will cycle on and off as needed to maintain this temperature. On a freezer, they have a defrost timer and defrost thermostat located in the system also. What I would like to know is the age and condition over all of the unit, to determine if maybe you have a small freon leak which does happen. Somethings you can check, is to pull it out to get behind it with the thermostat set to its coldest setting. With it unplugged, you should have a lower panel that you can remove to expose the compressor, the condenser coil, and coil motor. See how dirty this coil is as far as lint and dirt that has built up on the front of the coil. Clean it with a stiff bristle brush, not wire. It has to be clean for this motor to pull air back through it to keep the internal head pressures down on the unit. After you get all clean, plug it in as the stat is already to go and see if the compressor and this condenser fan motor comes on and runs. If the motor does not run, this will be your problem as it will be at fault and need replacing. Just spend some time back there and watch to see if the compressor continues to run. The air that you feel this motor pulling through the coil should be very, very, warm! If not, this indicates a loss of freon, and you have a leak. Try and time the compressor to see how long it runs before it shuts off only if the little motor is running, if you are up to it. It is difficult for me to tell you everything to check as we are limited on what you can do. I wish I were there. Anyway, let me know the things I have asked of you to do if you are able. You may just have a faulty thermostat control. We will go there later. Get back to me to let me know what is happening and if it freezes solid before it starts to defrost, and how far it defrosts, like all of the way.
Sincerely,
Shastalaker7
PS, I have to run for an hour or so, but will check as soon as I return. Good Luck

it would apear the stat is the fault. the thermostat is monitoring the temperature of the inner liner and tubing. if the compresor isnt actuly staying on the only part controling it is the stat. if you have the knoledge i would sugest you bypass the contol with the unit unpluged and the plug it in to conferm the fault was the control. p/s you may have a friend who has some knoledge . the control is a simple switch. just enshure the unit is unpluged. hope this helped

when its running how hot are the sides the starting amps are too high and 1.5 running amps ain't bad now the the cut in cut out are too high if you look on the dial that the mid point settings that's where you should have it not on 1 1 is hot set it on the straight line that's where you should do all your testing colder settings go up not down you could be overheating the compressor by making it come on too quick the freezer should be about -10 or so do you see any gaps in the gasket