Suggestions for Reefer Fans, Please

[Roy M]

I am installing a pair of small Radio Shack fans in my refrigerator to circulate cold air. I don't expect them to last forever, but I'm sure someone out there has done the same. They will be located inside 1 1/2" PVC pipes in the reefer to suck air from the cold plate and discharge it at the far end of the reefer, upwards. The distance is about 30" and the volume of the box is about 6 cubic feet. There are grills over the intake and output tubes (two tubes) to protect the blades. I am going to run them 24/7 to see what I can get out of them. Since the electrical demand is negligible, I'm not concerned about it. Still, if the circulation can be timed somehow, I'd like to know what units are available for this.

I'm also going to be installing much larger fans, probably about 6", to circulate air around the compressor and motor when it's running. Suggestions also requested for these units. I'll send pics shortly. Thanks!

[Vasco]

Jamicon JF 0625B for the reefer.



Jamicon Electronics Corporation - ???? ????

[Roy M]

Vasco, thank you. Do you have any experience with the HTLS bearing system? It seems to have a 100,000 hour rating. That's more than 10 years!

[Vasco]

I had one fan fail but I think that was user error as we somehow jammed it. The replacement has been running for eight years (6 months continuous use each year). The fans are relatively inexpensive. I don't know where to buy them but I phoned them in L.A. (I think) where their US office is and they sent me one they had as a sample in the office. They don't really sell them from that office and didn't take Visa or anything so I mailed them a check. Think it was $10. These are very nice fans, not the usual Radio Shack stuff.

I forgot to say earlier that it is a Adler Barber system and when I called them about a replacement fan they wanted $70!!! I searched and found the manufacturer.

[Cheechako]

is it a 12v fan? if so you can wire it into your reefer on/off cycle.

[Vasco]

Actually my spillover fan is wired to the fridge thermostat. Yes they`re 12v.

[Cheechako]

My question was for the OP. But sounds like you've got it setup well. I liked the little computer fans, so quiet and so little draw.

[Roy M]

Hey Cheechako, is the bridge passable yet? Yes, it's a 12 volt system, and my intended use for the fans is to circulate cold air from next to the cold plate to the back of the reefer compartment. At 6 cfm per fan, that's circulating all the air in the fridge in 30 seconds. Probably way overkill, so I'm considering some timer circuit that will do an acceptable job for fewer electrons. In the meantime, I'm going to try to fry these Radio Shack fans to get a sense of their longevity. The units Vasco has suggested are far superior, with either double ball bearing or something called HTLS bearings. I looked at the diagram and saw something that disturbs me, though. The drawing shows a PCB lubricant. I hope I'm wrong because having polychlorobiphenyls in a reefer doesn't strike me as the greatest idea in the world. http://www.jamicon.com.tw/index.php?...103&Itemid=259. The Radio Shack units are also overpriced.

[Cheechako]

Oh Yeah, the bridge is fixed! Temporary fix until they build a new section.
The little Computer fans used to be easy to find. Not sure now, as desktop units are yesterday's hardware. They draw almost nothing and last forever. I think you might be moving too much air so you do need to find a way to shut it off and on. Can you power it from your compressor control?
$4 here: http://www.coolerguys.com/8405560871...FUQ6QgodVh8Awg

[Roy M]

The compressor should only be operating a couple times a day, not enough to keep the temp even in the box. I guess I'll have to find some "project kits" that one can modify to make a timer.

[Cheechako]

engine drive compressor?

[Roy M]

No, Bitzer compressor with direct drive 1/2 HP 12 volt motor.

[Dsanduril]

I get the fans here (filtered to 12VDC). Lots of sizes, flow rates, and bearing types to choose from:

http://www.alliedelec.com/search/searchresults.aspx?dsNav=N:4294954022-4294886671

If you further the search they have half a dozen round muffin fans that may fit in your duct.

[Roy M]

Anduril to the rescue! Thanks, Don. Any ideas on a programmable timer?

[Roy M]

I'm thinking along the lines of on for a couple minutes, off for fifteen minutes, enough to stir up the cold air nearest the bottom of the cold plate and redistribute it to the other end of the box, near the top. Completely automatic.