Freezer Frosting Up Too Fast

[sailorboy1]

Originally Posted by Richard Kollmann

Then you need to determine if the evaporator is Adler Barbour's smallest evaporator which was the wrong evaporator in the beginning.

Doubt that as it is pretty big. C shape that is 16x13x16” and like 14” depth. It cover 90% of 3 walls of the freeze. It is also original to the boat and i doubt Hunter build 4 years of these with too small evaporator or i would have heard about it.

[Montanan]

Defrost Thermostat

If your frost-free freezer has frost buildup, particularly around the evaporator, there may be an issue with the defrost thermostat. This type of freezer has a defrost heater to melt frost from the evaporator coil to keep it from frosting over. The defrost thermostat supplies power to the heater, and signals the shut-off when the defrost cycle is complete. You can test the functionality of the defrost thermostat using a multi-meter; it should have continuity when at freezing temperatures, and should be open circuit when the temperature is above 37 degrees Fahrenheit. A lack of continuity means your thermostat will not power the heater, leading to frost in the freezer.

Door or Lid Gasket

If your freezer is frosting over, it may be due to a broken door lid or gasket. The gasket creates an airtight seal between the door and freezer cabinet to keep the air inside cold. If the gasket is damaged, it may be letting warm, moist air inside the freezer, which can result in frost when it comes in contact with the freezing cold surfaces inside. If the gasket on your frost-free model has a leak, frost can build up on the evaporator, which means the compressor has to run more than usual. Check the gasket for leaks or damage. If the frost is specific to one area, that is likely where the gasket leak is. Replace the gasket if you find any cracks or damage.

Defrost Timer

If you are noticing frost in your freezer, it may mean there is an issue with the defrost timer. In frost-free freezer models, a defrost heater is used to melt frost before it can build up on the evaporator coil. The timer signals the heater to turn on at regular intervals for efficient operation. If the timer is not working, the heater will not run as usual and the compressor may run continuously. You can turn on the defrost timer manually to begin the defrost cycle; if the other components work normally, that means the timer is defective and needs to be replaced.

[Richard Kollmann]

Originally Posted by sailorboy1

Doubt that as it is pretty big. C shape that is 16x13x16” and like 14” depth. It cover 90% of 3 walls of the freeze. It is also original to the boat and i doubt Hunter build 4 years of these with too small evaporator or i would have heard about it.

Sounds like evaporator is large enough so we are back to refrigerant loss or compressor speed question.
The speed resistor in AB thermostat if there is one is a small lump in wire about one inch from thermostat. if you watch the slide show on my web site you will see how to make several test plug in resistors to find best performance and lowest daily power consumption. If you ever need to replace control module buy the AEO module at an additional cost of $30, it will automatically find and keep the most efficient speed as ambient conditions change, while thermostat always maintains desired box temperatures.

[sailorboy1]

Except for a small loss of efficiency, why wouldn’t/shouldn’t i just take the resistor out of the and let the compressor run at max speed? I am more interested in cooling performance than the small extra power use.

[Coolerking]

Originally Posted by Montanan

Defrost Thermostat

If your frost-free freezer has frost buildup, particularly around the evaporator, there may be an issue with the defrost thermostat. This type of freezer has a defrost heater to melt frost from the evaporator coil to keep it from frosting over. The defrost thermostat supplies power to the heater, and signals the shut-off when the defrost cycle is complete. You can test the functionality of the defrost thermostat using a multi-meter; it should have continuity when at freezing temperatures, and should be open circuit when the temperature is above 37 degrees Fahrenheit. A lack of continuity means your thermostat will not power the heater, leading to frost in the freezer.

Door or Lid Gasket

If your freezer is frosting over, it may be due to a broken door lid or gasket. The gasket creates an airtight seal between the door and freezer cabinet to keep the air inside cold. If the gasket is damaged, it may be letting warm, moist air inside the freezer, which can result in frost when it comes in contact with the freezing cold surfaces inside. If the gasket on your frost-free model has a leak, frost can build up on the evaporator, which means the compressor has to run more than usual. Check the gasket for leaks or damage. If the frost is specific to one area, that is likely where the gasket leak is. Replace the gasket if you find any cracks or damage.

Defrost Timer

If you are noticing frost in your freezer, it may mean there is an issue with the defrost timer. In frost-free freezer models, a defrost heater is used to melt frost before it can build up on the evaporator coil. The timer signals the heater to turn on at regular intervals for efficient operation. If the timer is not working, the heater will not run as usual and the compressor may run continuously. You can turn on the defrost timer manually to begin the defrost cycle; if the other components work normally, that means the timer is defective and needs to be replaced.

Exactly zero of this post applies to the OP's issue.

[a64pilot]

Originally Posted by sailorboy1

Except for a small loss of efficiency, why wouldn’t/shouldn’t i just take the resistor out of the and let the compressor run at max speed? I am more interested in cooling performance than the small extra power use.

I believe it’s the other way around, the resistor speeds it up, no resistor and it defaults to slowest speed.

I’m still wanting to hear how incorrect refrigerant level can cause excess frost.
I will throw out another possibility, perhaps your not really getting all that much more frost, but due to low refrigerant level, it’s not cooling as well as it was, making it so that even a small amount of frost and it can’t hold temp.

Is that possible?

[a64pilot]

Originally Posted by Richard Kollmann

Sounds like evaporator is large enough so we are back to refrigerant loss or compressor speed question.
The speed resistor in AB thermostat if there is one is a small lump in wire about one inch from thermostat. if you watch the slide show on my web site you will see how to make several test plug in resistors to find best performance and lowest daily power consumption. If you ever need to replace control module buy the AEO module at an additional cost of $30, it will automatically find and keep the most efficient speed as ambient conditions change, while thermostat always maintains desired box temperatures.

The AEO module is pure magic, it has to be experienced to believe it. Right now my BD80 14 cu ft spillover is running and drawing 4 amps. That’s because we haven’t added any food in a few days and everything has reached equilibrium and the AEO has throttled back to provide just the right amount of cooling.
To put that in perspective our Engle 40 qt cooler is I think 1.5 cu ft or so and draws 3 amps, but it’s also used as a deep freeze.
If we add a bunch of food, it will over time draw at least twice this amperage to cool things down, but it only uses the amount of current it needs, no more.
It’s also a soft start, you can watch that as it draws maybe 3 amps when you turn it on and slowly will draw more, and I don’t notice any noise on the SSB, where my old non AEO controller made silly 1950’s SciFi space noises.
I would tell anyone to buy an AEO module even if they don’t need it and consign the non AEO one to spares.
You need a spare module, unless your where you can get one in a hurry.

[Richard Kollmann]

Originally Posted by a64pilot

I believe it’s the other way around, the resistor speeds it up, no resistor and it defaults to slowest speed.

I’m still wanting to hear how incorrect refrigerant level can cause excess frost.
I will throw out another possibility, perhaps your not really getting all that much more frost, but due to low refrigerant level, it’s not cooling as well as it was, making it so that even a small amount of frost and it can’t hold temp.

Is that possible?

To much refrigerant can result in moving refrigerant phase change to exit line of evaporator.

Lack of large amounts of refrigerant causes frost where it should not be or no frost.


If slightly low on refrigerant evaporator can display frost but heat absorbing mass is reduced resulting in lower heat energy removed. The first indication of small refrigerant loss on a cap tube flow system is a reduction in amperage. This should not be confused by very low evaporator temperature and low amperage as low temperature also lowers the mass flow passing through evaporator. The same evaporator operating in a refrigerator will have its refrigerant flow cut in half when operated as a freezer evaporator.

Refrigerant mass flow on a system with a refrigerant receiver tank and TXV valve should not be confused with a capillary flow control tube.

Frost in a refrigerated box results from moisture already in box and infiltration of outside moist air. Is excessive evaporator frost an insulator? the answer is YES. How much frost is too much in your boats non self defrosting refrigerator depends on use of available space and amount of on board energy available to maintain desired box temperature.

[sailorboy1]

It frosted up enough to effect the temperature in 2.5 days. It works great till then.

It just that it has to be be lid seals. There is water on the inside surface of the freezer lip (top loading) and an ice tray i put in there hasn't frozen (it has a cover plus i put it in a freezer bag).

I have tried at least 3 different seals. Does anyone have a recommendation for different ones?

[Happydrv]

I found a fan speeds up the frost and also the drop in temp when you put new groceries in. Shut mine off, replaced the thermos with a digital and all runs much better now.
Best advice I was given was to spray the frosty surface, in my case a plate, with PAM when defrosted. After that the frost just falls off when defrosting. Then I wipe it off and freshen up the PAM. Works fabulous!

[David Mathis]

The same thing happened a couple years ago with my Norcold freezer which had been trouble free for several years. Rather than try to analyze and fix the problem, I called the refrigerator repair shop. The repairman replaced a part that had failed and it’s worked fine since then. I asked if it was something I could have fixed myself. He said it couldn’t be fixed without replacing the failed part. Sometimes it’s best to save the effort and frustration and just call a repair shop.

[Vger]

A/C units will frost up excessively when the system loses coolant pressure. This happens because of the higher pressure drop at the evaporator coils. The other symptom to low coolant pressure could be longer compressor run time. As more leaks out, more frost will form. Path may be to consider you have a slow leak and have the refrigerant recharged.

[sailorboy1]

I have, and continue to, consider a refrigerant loss. The thing that kind of talks me out of it s that problem really got worst a year ago and if there was a leak I would think it would have all leaked by now.

On yesterdays defrosting i took all screws out of the walls and lids and resealed them. Some did seem to need it, but they don't seem to be enough to cause the problem. Will find out in a few days.

[Bill O]

Originally Posted by sailorboy1

It frosted up enough to effect the temperature in 2.5 days. It works great till then.

It just that it has to be be lid seals. There is water on the inside surface of the freezer lip (top loading) and an ice tray i put in there hasn't frozen (it has a cover plus i put it in a freezer bag).

I have tried at least 3 different seals. Does anyone have a recommendation for different ones?

Gave you recommendations for sources of custom magnetic seals in your other thread. They were not that expensive, especially #3 in the group I sent.

You mentioned you've tried 3 so far. What were they and were they continuous or did you cut segments? Is it a single gasket or tiered sets?

[sailorboy1]

It has been 24 hours since yesterdays defrost event where I also went through and caulked screw fittings etc. and it is looking good. I have my toes crossed. But there isn't anything to say for a couple more days.

The “has to be the lid seals” isn't really true. It could be the the screws for the latch and lid trip fitting and this is the first time i gave them consideration.

I have tried cut and continuous seals. I currently have a foam weather strip also and can see that the lid is contacting it over entire length, so it should be sealed.