Increasing Airflow through Condenser.
The new DC only compressor fridge I will soon have in my possession has a 92 mm computer muffin fan pulling air through only a portion(~85%) of the ~120mm tall condenser. It then blows this warmed a...
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Thank you very much.
The fan current is limited to .5 amps (1 amp for upto 2 seconds) according to the Danfoss PDF sheet I was just studying. The fan is positioned so it is level with the top of the condenser, so the lowest tube and fins are not directly in the airflow of the fan.
I was not so much interested in putting a much more powerful fan in as one that actually pulls air across the whole of the condenser. For that I would need to build a shroud. The 92mm fan it comes with is, I believe, ~38 cfm and 25db and I can find a same size one at 42 cfm and 15 db. I could also fit in a larger fan that moves even more air for less amps and noise, and would make fabricating the shroud easier too.
I did see in the Danfoss PDF that the compressor can be speeded up from the minimum 2000 rpm by adding a resistor to the thermostat circuit. Perhaps at faster speeds there would be more benefit to a much faster CFM fan and the compressor would run less frequently.
Thank you for confirming that the direction of flow through the condenser is better from left to right, and that the warm air on the compressor is of no benefit.
With the extra insulation I plan on adding and this added airflow, I bet I can achieve a very efficient fridge.
That Grainger fan is ridiculously expensive. You can find similar CFM fans in that size for significantly less, though I cannot vouch for their durability.
Here are some sites to browse for fans:
Frozen CPU
190 cfm dual ball bearing 4.75 inch/ 120mm 12 volt fan.
These fans are super loud when they spin 4000 rpm. You can get larger ones (180/200/220 and 360mm) which move move nearly as much with less noise and amp draw.
I have a 12vdc 92 mm fan (Vantec tornado) which spins 3800 rpm and is rated at 1 amp 118 cfm. The first time I hooked it to 12 volts, it sucked itself right across the table, screaming. Highly recommended!
I have it wired to a voltage controller and to an adjustable arm with a good clamp and run it from 3 to 12 volts in 1.5 increments. With the fixed curved blades in front of the spinning fan concentrating the flow, it sends a dense column of air wherever I point it. Very impressive flow, and at 9 volts, it only pulls .5 amps.
The fan current is limited to .5 amps (1 amp for upto 2 seconds) according to the Danfoss PDF sheet I was just studying. The fan is positioned so it is level with the top of the condenser, so the lowest tube and fins are not directly in the airflow of the fan.
I was not so much interested in putting a much more powerful fan in as one that actually pulls air across the whole of the condenser. For that I would need to build a shroud. The 92mm fan it comes with is, I believe, ~38 cfm and 25db and I can find a same size one at 42 cfm and 15 db. I could also fit in a larger fan that moves even more air for less amps and noise, and would make fabricating the shroud easier too.
I did see in the Danfoss PDF that the compressor can be speeded up from the minimum 2000 rpm by adding a resistor to the thermostat circuit. Perhaps at faster speeds there would be more benefit to a much faster CFM fan and the compressor would run less frequently.
Thank you for confirming that the direction of flow through the condenser is better from left to right, and that the warm air on the compressor is of no benefit.
With the extra insulation I plan on adding and this added airflow, I bet I can achieve a very efficient fridge.
That Grainger fan is ridiculously expensive. You can find similar CFM fans in that size for significantly less, though I cannot vouch for their durability.
Here are some sites to browse for fans:
Frozen CPU
190 cfm dual ball bearing 4.75 inch/ 120mm 12 volt fan.
These fans are super loud when they spin 4000 rpm. You can get larger ones (180/200/220 and 360mm) which move move nearly as much with less noise and amp draw.
I have a 12vdc 92 mm fan (Vantec tornado) which spins 3800 rpm and is rated at 1 amp 118 cfm. The first time I hooked it to 12 volts, it sucked itself right across the table, screaming. Highly recommended!
I have it wired to a voltage controller and to an adjustable arm with a good clamp and run it from 3 to 12 volts in 1.5 increments. With the fixed curved blades in front of the spinning fan concentrating the flow, it sends a dense column of air wherever I point it. Very impressive flow, and at 9 volts, it only pulls .5 amps.
