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Old 28-08-2016, 08:08   #31
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Re: Frig using too much power

You might get more help if you stop writing critiques of responses
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Old 28-08-2016, 08:36   #32
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Re: Frig using too much power

Quote:
Originally Posted by johnr9q View Post
(When the compressor runs constantly it uses 5.9 amps which means it should run 42 percent of the time at 2.5 amps)
Did the manufacturer state that?
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Old 28-08-2016, 08:48   #33
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Re: Frig using too much power

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Did the manufacturer state that?
Yes, that is what the manufacturer states and that is also what my ammeter confirms.
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Old 28-08-2016, 09:00   #34
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Re: Frig using too much power

Quote:
Originally Posted by johnr9q View Post
Yes, that is what the manufacturer states and that is also what my ammeter confirms.
That means the compressor is within specs but duty cycles are longer than usual. Again, I reckon because of the high ambient temps.
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Old 28-08-2016, 09:51   #35
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Re: Frig using too much power

Quote:
Originally Posted by johnr9q View Post
Yes, that is what the manufacturer states and that is also what my ammeter confirms.
Curious, and what are the ambient, freezer and fridge temperature when running at 5.9 amps?

Quote:
Originally Posted by johnr9q View Post
Questions
Dometic is not a small job shop.

Dometic absorption fridge work surprisingly very well near a 50C ambient and much better than BD type compressor.

Fridges designed for warm climate does not need to be in an air-conditioned environment but will perform better in an air conditioned environment. With care (door opening, etc} a duty cycle of 80 to 90 % versus 50 to 60 % can be experienced.
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Old 28-08-2016, 10:19   #36
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Re: Frig using too much power

Is the heat exchanger near the compressor clean and dust free?
Does it have ample air flow?
These compressors use very low pressure. If someone overfilled it, which is very easy to do, the current will be high and it will not cool as well as it should.
Kollmann Marine Can answer your questions by a professional that works on and understands marine refrigeration.

If I have helped you please click on the "Thanks" icon in the lower right corner of my post.
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Old 28-08-2016, 12:44   #37
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Re: Frig using too much power

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Originally Posted by chala View Post
Curious, and what are the ambient, freezer and fridge temperature when running at 5.9 amps?



Dometic is not a small job shop.

Dometic absorption fridge work surprisingly very well near a 50C ambient and much better than BD type compressor.

Fridges designed for warm climate does not need to be in an air-conditioned environment but will perform better in an air conditioned environment. With care (door opening, etc} a duty cycle of 80 to 90 % versus 50 to 60 % can be experienced.
If the Fridge ran at 5.9 amps it would be running full time and I don't know what the freezer or Fridge temps would be
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Old 28-08-2016, 13:17   #38
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Re: Frig using too much power

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Originally Posted by Miniyot View Post
Is the heat exchanger near the compressor clean and dust free?
Does it have ample air flow?
These compressors use very low pressure. If someone overfilled it, which is very easy to do, the current will be high and it will not cool as well as it should.
Kollmann Marine Can answer your questions by a professional that works on and understands marine refrigeration.

If I have helped you please click on the "Thanks" icon in the lower right corner of my post.
1. The heat exchanger is very clean.
2. The system was charged at the factory and the unit is only a few months old, so as far as I know, this should be good
3. As far as I can tell the compressor has ample air flow. There is 2 1/2 inch of space between the back of the fridge and the rear of the fridge cabinet. (The installation instructions say a 2" space is required). At the bottom of this space is a louvered vent that measures 19" x 11" and at the top of this space there is a louvered vent that measures 19" x 6". Both vents, vent to the outdoors.
4. Kollmann replied to this post and I also sent them a personal message so I am open to any response they have. I selected email on their site and couldn't get anywhere, as far as contacting them.
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Old 28-08-2016, 14:58   #39
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Re: Frig using too much power

You took a temperature reading of the outside ambient temp.
Did you take one close to the compressor?
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Old 28-08-2016, 19:46   #40
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Re: Frig using too much power

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If the Fridge ran at 5.9 amps it would be running full time and I don't know what the freezer or Fridge temps would be
If the amount of heat pumped out by the compressor is equal to the amount of heat entering the fridge, the fridge will run full time at any working temperature.
For example: My ageing brain tells me that if the fridge run non stop (100 %), at 90 degrees, Freezer 0 degrees and frig 41 degrees, the current will remain at 2.5 amps.
And not go to 5.9 amps.
Your observation is that The compressor ran 69% of the time.
That is, the amount of heat entering the fridge is less than the amount pumped out by the compressor.
To assume this,

Quote:
Originally Posted by johnr9q View Post
(When the compressor runs constantly it uses 5.9 amps which means it should run 42 percent of the time at 2.5 amps)
is incorrect.

Also for the compressor to cycle off, the temperature in the fridge freezer needs to go below the set point say Freezer 0 degrees and frig 41 degrees and above to cycle on. The current will change accordingly. Short cycling can damage a compressor motor. For that reason the thermostat controlling the compressor must have a suitable differential.
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Old 29-08-2016, 05:27   #41
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Re: Frig using too much power

What are others results? (Are the specifications for the Frig way to optimistic?)

YES.
40 amps a day if you are lucky. 60 amps a day happens.
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Old 30-08-2016, 08:50   #42
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Re: Frig using too much power

Quote:
Originally Posted by chala View Post
If the amount of heat pumped out by the compressor is equal to the amount of heat entering the fridge, the fridge will run full time at any working temperature.
For example: My ageing brain tells me that if the fridge run non stop (100 %), at 90 degrees, Freezer 0 degrees and frig 41 degrees, the current will remain at 2.5 amps.
And not go to 5.9 amps.
Your observation is that The compressor ran 69% of the time.
That is, the amount of heat entering the fridge is less than the amount pumped out by the compressor.
To assume this,



is incorrect.

Also for the compressor to cycle off, the temperature in the fridge freezer needs to go below the set point say Freezer 0 degrees and frig 41 degrees and above to cycle on. The current will change accordingly. Short cycling can damage a compressor motor. For that reason the thermostat controlling the compressor must have a suitable differential.
I don't understand what you are talking about. You said "if the fridge run non stop (100 %), at 90 degrees, Freezer 0 degrees and frig 41 degrees, the current will remain at 2.5 amps." If it takes 5.9 amps to run the fridge and the fridge runs full time it takes 5.9 amps to run the fridge. Why do you say the current will remain at 2.5 amps?
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Old 30-08-2016, 08:59   #43
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Re: Frig using too much power

Quote:
Originally Posted by Scaramanga F25 View Post
What are others results? (Are the specifications for the Frig way to optimistic?)

YES.
40 amps a day if you are lucky. 60 amps a day happens.
Can you tell me how you got your information? If my fridge only used 60 amphours a day I would be happy. That would mean the fridge is running less than half the time. (The fridge uses 5.9 amps and if it used 60 in a day I would divide 60 by 5.9 and get 10.2 hours the fridge is on. 10.2 divided by 24 equals 42%, meaning the fridge would only run 42% of the time
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Old 30-08-2016, 09:06   #44
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Re: Frig using too much power

The rated amps are seen only on a hot system. After that the system may go into steady state and run continuously, but at a lower amp draw because the compressor isn't working so hard because the return gas is lower pressure.

But I don't think you want an answer, you want some easy magic bullet.

My system uses 60 AH/day in the spring and fall when it is cooler out. The last month or so with it being so hot out it has used 80+ AH/day.
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Old 30-08-2016, 09:58   #45
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Re: Frig using too much power

Just don't let the beer get warm. 42 sound about right.
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