How to rig up a fan for my keezer?

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Beavdowg

Beavdowg

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I recently got a chest freezer and am thinking about puttinga CPU fan inside it to help with the cool air circulation. I've read of others doing this. My question is how do you wire the fan into the system? Is the fan always on or does it come on only when the freezer turns on? I am not an electrician whatsoever so if this aint easy it just won't happen. Can you just plug in one of those "2 plugs into 1" into the temp controller so that when the temp controller turns on the freezer it turns on the fan also?

thanks:mug:
 
computer fans are normally 12v dc current. I think you are on teh right track with turning it off and on with the freezer. So when the compressor turns on the fan turns on so its not on alllll the time. Your issue is getting from 120v AC to 12v DC. I read about someone using an old cell phone charger and just splicing that straight to the fan. It would work but most cell phone chargers run at like 5v, which means your fan will run close ot half speed. This is probably fine and a cheap fix.

Just a thought!
 
easy solution.....buy a 9 volt plug at radio shack, twist the bare ends with the fan leads and electric tape. Plug the 9 volt on. This will be on all the time. I'd imagine a simple fan should last a while. You could also unplug the battery or put in a simple switch for when you won't be using the keezer for a while. This is as easy as it can get work and knowledge wise.
battery_lg.jpg
 
springer said:
I just used a cell phone charger and drilled a small hole in the collar its on all the time.
Click to expand...

Same here. My theory on this is:

1) You want circulation in there even if the compressor is not on, to keep things as stable as possible, esp. since the compressor should only be turning on every so often any way.
2) CPU fans are sort of made to run a lot.
3) CPU fans are cheap.

Edit: IrregularPulse's idea seems really good too. Wish I had thought of that--my fans would be more mobile, and it would be easier to move them into good positions to get maximum circulation... Any idea how long would a battery would last?
 
IrregularPulse said:
easy solution.....buy a 9 volt plug at radio shack, twist the bare ends with the fan leads and electric tape. Plug the 9 volt on. This will be on all the time. I'd imagine a simple fan should last a while. You could also unplug the battery or put in a simple switch for when you won't be using the keezer for a while. This is as easy as it can get work and knowledge wise.
Click to expand...

Average 9V battery has about 400-600 mAh. Average 80mm fan draws 150-200 mA at 12v, or 112-150 mA at 9v. Your 9v battery will only last a max of 6 hours, and probably more like 4 hrs, running a computer fan....
 
One of these will run for a month on 2 D cells. Get rechargeable ones.

Reefer fan

31057.jpg


My fans are wired into an old laptop brick. When I setup my Ranco, I used a power strip instead of an extension cord, so I've got six outlets. They only run (to supply cooling to the conditioning cabinet) when the compressor is on.
 
I installed a 110v AC muffin fan in my converted freezer. I mounted it to the underside of the lid using toggle bolts and some nylon spacers to allow for air flow between the fan and the lid. Ran the power cord through the collar. It runs full time and consumes only 22 watts of power. IMO, it's best to keep the fan running continuously in order to maintain the most constant temperature throughout the freezer compartment. This also keeps the taps and beer lines at near the same temperature as the kegs and the kegs are more uniformly cooled from top to bottom. I would estimate the cost to run the fan continuously at about 5 or 6 cents per day. Obviously, this may vary a little depending on your local power costs, but in any case, it ain't much at all. This mod to my converted freezer was a huge improvement. It was also very easy to do and didn't cost much at all. I highly recommend it. The same mod could be done with a DC fan and a cell phone charger with the right output. You won't believe the difference it makes.

4187313347_c089ea8e64_b.jpg


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I used a 12V CPU fan in a project box from radioshack with a tube running up into my tower. I powered it using a cell phone charger and plugged it into one of those light timers. You can set it to come on and off whenever you want.
I usually have it turn off at midnight and back on around 11am.
 
metaltim said:
can you take a pic of the other side of that wire, for the electrical dummies? where does that wire go?
Click to expand...

Look at the collar just below the fan and you can see the power wire for the fan and also the controller probe. The fan simply plugs into a power strip mounted on the wall behind the freezer.
 
Metalism, the probe is just sitting there under the fan? don't you get a lot of cycling on/off with the compressor?
 
A 12V PC fan is what you want, always on, running off of any wall-wort up to 12V--cell phone chargers are good, esp. 5-9 volts or so. Also spend $5 at Lowes for a piece of aluminum flexible duct and duct tape your PC fan to one end, bend a small "L" in the other and stand that beautiful boy up in one corner of the low section with the fan at the top. Drill a small hole or pass wires through with your gas line if the bottle is outside.

It will gently pull that frigid air out of the bottom all the time--maintaining a surprisingly even temperature and minimizing swing between on/off cycles. AND it will make almost no heat (watts--less is way better in this case). Perfect. It took me many many iterations to get to what any reasonable person would have tried the first time.

IMG_4368.jpg
 
slakwhere said:
Metalism, the probe is just sitting there under the fan? don't you get a lot of cycling on/off with the compressor?
Click to expand...

Yep, the probe is deliberately mounted directly in the air stream of the fan and the fan runs full time. The cooling cycle is not excessive and the power consumption is only about 1/2 kwh/day @ 72F ambient. I've experimented with just about every imaginable configuration and I like this arrangement best so far.
 
Yes, I know this is an old thread. But for anyone looking for info, I mounted an AC muffin fan on the underside of my keezer lid. I also wired a waterproof switch inline so I can easily toggle power on of off when the lid is open for cleaning or swaping kegs.

1704682681551.png


1704682711057.png


 
I think Muffin was a brand name at a time and just became common lingo, like Kleenex, despite what you use may not actually be using Kleenex.

That said, why they picked it as a brand name I don't know.
 
"Muffin fan" would date most folks to at least my age of decrepency 😁
It actually refers to that same square shape fan but back in the stone age of unpainted aluminum it was said to look like a cup in a muffin pan...

Cheers! (I never got it...)
 
When I put my keezer together at our city house, a couple of years ago, I used one of these. I just removed the fan from its base and laid it on its back, on the hump, next to the C02 bottle. It’s low voltage, runs off a wall wart with a USB cable and is on all the time. It’s very quiet and keeps the interior dry.
 
In my old keezer that died, I had a PC fan and it worked well. I wired in the female side of the PC board connector to a DC power adapter and just ran the wire between the lid gasket and the top of the keezer.

While this seemed to work well, I had to manually unplug the thing if I needed the lid open for maintenance stuff. Otherwise it would blow all the cold air out due to the way it was mounted.

So I wanted a switched solution and chose the AC fan route. It defiantly feels like solid solution but probably doesn't work any better than any other simpler/cheaper routes. But its what I did and I'm happy with it.

I was careful to create a drip loop on the wiring to the fan itself and use a waterproof switch that's insulated on the toggle. AC in a potentially damp area can be scary. But I'll have Eva-Dry inside too to help keep things from getting too damp.
 
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With 9-12V wall warts being dime a dozen, so to speak, that's what I use for circulation w/12V fan. As well, 12V PWM controls are cheap too if you want to introduce some degree of variable speed.
 
IMG_0414.jpeg

Cut out some Perspex, clamp it, chop out suitable hole for fan with large hole saw, drill screw holes to fix fan, clamp between two scrap pieces of wood where you want it to bend, heat it with an electric heat gun (quite high temp, it can take it), bend when it will then support it while it cools for a minute or two, stick it with Gorilla tape.
 
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Thats very clean! What you did with the temp probe is exactly what I'm wanting to do as well. Do you mind sharing info on how thats constructed?
 
Nagorg said:
Thats very clean! What you did with the temp probe is exactly what I'm wanting to do as well. Do you mind sharing info on how thats constructed?
Click to expand...
To be honest, I stopped using the temp probe there. It’s better in stuck with insulation to the side of a keg or FV, or in an FV thermowell. In the repurposed yeast vial, even with glycerol, I found it pinged back and forth more than I wanted.
 
McMullan said:
It’s better in stuck with insulation to the side of a keg or FV
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LOL... I've read enough posts that had me thinking that may be the case. In my last keezer, I had the probe sandwiched between a water bottle and two koozie layers. To the best of my knowledge, that worked fine. I just cant help but think that having the probe in a thermowell (in a small container to improve temp change response) should be "better". Seeing your pic bubbled this notion up in my head again.
Guess I'll revert to the tried and true K.I.S.S. principle.
 
Indian_villager said:
to cut down the noise.
Click to expand...

I'm definitely getting more noise than anticipated from the AC fan I used. Its not really that loud but there is a noticeable hum; certainly more that I'd like to have. Its not helping the WAF (Wife Acceptance Factor).

The model I used is marketed as "quiet" at 32 decibels. According to decibel charts that's slightly above a whisper at 30. Maybe its the tone or amplification from the keezer lid and minor vibrations. I used rubber washers between the standoffs and the lid in an attempt to reduce things like this.

Not sure a DC fan would be any quieter unless slowing down the speed would help. The AC fan is an AC Infinity LS1238 "low speed" model though.

**UPDATE: I ordered a fan speed controller from AC Infinity. Hopefully this will help me reduce the noise.
 
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Nagorg said:
I'm definitely getting more noise than anticipated from the AC fan I used. Its not really that loud but there is a noticeable hum; certainly more that I'd like to have. Its not helping the WAF (Wife Acceptance Factor).

The model I used is marketed as "quiet" at 32 decibels. According to decibel charts that's slightly above a whisper at 30. Maybe its the tone or amplification from the keezer lid and minor vibrations. I used rubber washers between the standoffs and the lid in an attempt to reduce things like this.

Not sure a DC fan would be any quieter unless slowing down the speed would help. The AC fan is an AC Infinity LS1238 "low speed" model though.

**UPDATE: I ordered a fan speed controller from AC Infinity. Hopefully this will help me reduce the noise.
Click to expand...
The fan you posted has a rated speed of 1800RPM, the ones I'm using max out at 1350RPM and from there I have it cut down to about 50% output. A bigger fan spinning slower is going to be more efficient for noise/performance ratio.
 
Indian_villager said:
A bigger fan spinning slower is going to be more efficient for noise/performance ratio.
Click to expand...

Understood... Not sure I'd want a much bigger fan in my keezer. This fan isn't as fast as some PC fans I've seen but definitely agree that slowing it down should help. I'll find out soon, my controller should arrive today.
 
Nagorg said:
Understood... Not sure I'd want a much bigger fan in my keezer. This fan isn't as fast as some PC fans I've seen but definitely agree that slowing it down should help. I'll find out soon, my controller should arrive today.
Click to expand...
Oh your size fan is fine, this was a general comment for those considering smaller fans. For my fist iteration I tried going with 40mm fans and immediately regret my decisions.
 
I made two strips of wood and screwed a variable-speed AC fan to them. Then I applied Velcro strips to the wood, and I stuck matching strips to the underside of my keezer lid. If the fan dies, I rip it off, put the wood strips on a new fan, and move on with life. I thought the Velcro might eventually pull loose from the weight of the fan, but after a year, nothing has moved.

02 18 23 keezer fan on lid small.jpg


I never bothered cleaning up the cord.

I saw a Northern Brewer video, and their company keezer looks like baboons built it. This kind of killed my motivation to make everything look perfect.

The collar on my keezer is a "temporary" one I build a year ago. It looks too good to replace. My wife actually believed I ordered a complete keezer, with collar and taps. She was amazed when she learned I built it. Seems like a B- job to me, but any wife who thinks a keezer looks good is not to be contradicted.
 

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