Is my chest freezer about to die on me?

[ICWiener]

I'll just say it up front: I know nothing about refrigerator/freezer technology, so any help is greatly appreciated.

I bought a chest freezer off of craigslist a year and a half ago. It's biiiig. I haven't measured, but it's probably bigger than 20 cubic ft. It'll hold ten 5 gallon carboys at once. Anyway, lately it's taking significantly longer to bring my beer temps down. It's still getting cold, and ice still builds up on the wall when it's cooling for more than an hour. So it's working for now...but the problem is that if I put a carboy of wort in at, say, 70 degrees it takes almost 8 hours to get it down to 64.

I have my Ranco set at a 1 degree range. The freezer used to be able to knock that one degree back down in 10 minutes. Now it takes 20-30. And it sounds a little funny. It still has it's normal hum, but it also kind of sounds like there's running water in there or something. It's hard to describe.

So, is it dying? Should I be looking for a new unit? Or is it just losing efficiency with age? I really don't want to buy a new one because I know that I'll never find another one this big for a decent price, but I'm not going back to swamp cooling!

Thanks in advance for any help or advice.

 

[forstmeister]

Mine did the same thing...right before it died. It sucks but it will probably cost more to have repaired than to replace.

 

[ICWiener]

Not what I was hoping to hear!

I kind of assumed there was something wrong. I wonder if it's a good idea to attach an AC unit to the freezer. Just keep the shell, since it's such a good insulator.

 

[forstmeister]

Not what I was hoping to hear!

I kind of assumed there was something wrong. I wonder if it's a good idea to attach an AC unit to the freezer. Just keep the shell, since it's such a good insulator.

Maybe one of those free standing units they make now? Never thought of that.

 

[ICWiener]

Maybe one of those free standing units they make now? Never thought of that.

Yeah. I was thinking, why not just drill a hole in the wall of the freezer and feed a hose into it, straight from the AC. It would be cheaper than buying another freezer. A new 24 cubic ft unit costs more than $1,000!

 

[forstmeister]

Yeah. I was thinking, why not just drill a hole in the wall of the freezer and feed a hose into it, straight from the AC. It would be cheaper than buying another freezer. A new 24 cubic ft unit costs more than $1,000!

I bought a 5.3 CF at the local grocery store for$170. It came with $170 worth of food coupons too. It is big enough to keep 2 corny kegs without a collar. I am go an put a 2X10 collar on it so I can get another keg in on the hump.

 

[atreid]

Not what I was hoping to hear!

I kind of assumed there was something wrong. I wonder if it's a good idea to attach an AC unit to the freezer. Just keep the shell, since it's such a good insulator.

If you end up drilling, make sure you don't puncture the refrigerant piping. It might not be safe, especially with a very old freezer...

 

[ICWiener]

If you end up drilling, make sure you don't puncture the refrigerant piping. It might not be safe, especially with a very old freezer...

I suppose that could be a problem! I know that the coolant runs across the front wall of the unit. That's where the ice builds up when it's running. It might be safe to drill through one of the sides. Wonder if there's any way to tell?

 

[ICWiener]

Okay, so I've been doing some reading. Looks like drilling through the wall of a chest freezer is a very bad idea. Not only are there condenser coils, but also evaporator coils. Seems like you'd be bound to hit something.

Hmmmm....I wonder if drilling through the lid would work?

 

[Monster Mash]

I have my Ranco set at a 1 degree range. The freezer used to be able to knock that one degree back down in 10 minutes. Now it takes 20-30.

That 1 degree differential is probably what did it in, they don't like to be cycled like that.

 

[ICWiener]

That 1 degree differential is probably what did it in, they don't like to be cycled like that.

Doesn't everyone set their fermenter like that? You don't want actively fermenting brews to be swinging 5 degrees in temperature.

Regardless, the way I see it, it doesn't matter much in the Summer. If I set it to 64 with a 1 degree differential it'll kick on at 65. If I set it to 64 with a 5 degree differential, it'll kick on at 69...and as soon as it gets to 68 it will stop. then it will just cycle on and off at that temp, instead of at 64/65. So then I'm back to a one degree differential, right?

 

[Junkster]

No, if you set it to 64 with a 5 degree differential and it comes on at 69, it will run until the temperature drops to the setpoint which is 64. The temperature of a liquid would most likely settle out in the midpoint of the cut-in and cut-out points or 66-67.

 

[ICWiener]

The temperature of a liquid would most likely settle out in the midpoint of the cut-in and cut-out points or 66-67.

Even if your probe is set to read the temperature of the liquid itself?

 

[Junkster]

Yep

 

[ICWiener]

That doesn't make any sense to me...if you're measuring the temp of the liquid and you have it set to 64, you're saying that the temperature will drop until the probe reads 64, but the liquid will actually be 66 or 67. But the probe is in the liquid. What am I not getting here?

Either way, I think I might just buy a $100 window AC unit and pump the air into the fermenter. Just use the freezer as an insulated holding tank when it finally kicks.

 

[Whsoj]

I would go purchase a black and decker mini fridge and change over the coils and kompressor you could lose that plugin temp controller unit and keep the one for the fridge. You'd have a smaller kompressor that could hold higher temps easier. Freezer kompressors are work horses. You don't see people get a massive d12 cat bull dozer to spread gravel. It more than likely killed it starting up every 20 min just to run for five and shut off.

Edit : if you pump air into the freezer it has to come out some how.

 

[ICWiener]

I would go purchase a black and decker mini fridge and change over the coils and kompressor

Sounds tricky. Is that something anyone can do? Or would I need to get someone with some knowledge to help me out.

It more than likely killed it starting up every 20 min just to run for five and shut off.

I see what you're saying. Although I thought I was in the clear. It didn't run at all during the winter and during the summer it only kicks on once every 1-2 hours. In all honesty, I think it's just old. It had been used heavily before I bought it.

 

[sennister]

Yeah you will have to have an air input and exhaust. The exhaust can be in the lid easy enough. It would be nice to get a portable unit that had a duct hose so you could direct it where you want into the lid. The problem I see is that I am not sure how you will control it. You may be planning on using your existing thermostat from when you modified the freezer. The problem is that most of the AC units are digital and your t-stat will be cutting and supplying power to the AC unit as needed. However when the power kicks on if it is a digital unit will it remember what setting you had it on or will you have to press the buttons on it to turn it back on? Maybe you can find one with manual controls. That would be best if you can find one.

As for the T-stat. You would be better off to measure the air inside the unit not the liquid. The liquid will match the air temp over time. When I ferment in the winter I do this in my porch because we have electric baseboard heat out there. I set the room temp what I want the fermentation to be at and walk away. It will get to that temp and stay there. Liquid doesn't change temp as quickly as air. Look at lakes up here in MN and other northern states. It can be well below freezing in the fall but there is no ice on the lakes for many weeks. Same thing in the spring, It takes a lot of warm days to melt off the ice pack. So what happens in your case is you put the probe on that new batch of beer you put in the freezer. Lets say it is at 75 but you want it at 62. Ok fine, the compressor kicks in and it will run until it gets down to 62. Sounds good, but here is the issue. How cold did the air get in there while trying to get it to 62? Do you have other things in there at the same time fermenting? They may be way colder than you want you wouldn't know because you are measuring off the hottest thing in the freezer. Now you hit your target temp of 62 in the liquid of what you are measuring. If you have a well insulated freezer (most chest freezers are) what is that air temp at? Lets say it is at 40 and it isn't all that hot out or it is in your basement. The compressor may have cut off when the liquid reached 62 but it will keep chilling swinging you way too low until the two meet and slowly come up to the cycle range you have set. 62 with a 1 degree differential.

If you are measuring the air in the box however, you will run the compressor until it gets to 62 then run off the differential. Eventually the two will meet. If it is taking too long then next time you need to get your wort closer to your desired fermentation temp before moving it to the freezer. Get it down to 60-65 degrees and you would be better off. Remember though liquid holds the temp better than air so you are better off in the long run doing what was mentioned in another post and set the temp to 59 or 60 with a differential of 5 degrees. Your compressor will run less often making it last longer. Your liquid will sit about in the middle of the range at around 62 which is what you want. While it will take longer to get to temp, it will be a gradual drop to the desired temp followed by slight variations. Your air temp can swing a lot more than you think before impacting liquid temp. Sure by doing a liquid temp measurement with a tight differential would give you the same duty cycle of the compressor. But the problem is that the air still has to get much colder to drop it that degree and I suspect you are having a bigger swing on the liquid temp on the low side than you think. The thermostat just looks at if the measurement is above the desired setting and kick in. Once below it doesn't care how far below as it is only concerned about cooling.

So what can you do at this point? I would start by making sure your coils are clean. Many people don't bother cleaning them. Then measure off the air with a wider differential like mentioned. That might extend what life you have left. As mentioned it won't be worth it to fix it once it is dead. Some units have fans that blow across the coils. Make sure that is working if there is one.

Hope that helps some.

 

[ICWiener]

It does help quite a bit. Thank you. I do have other beers in the freezer at all times. I've currently got seven full carboys in it. 4 of those are sours, so they never move. They can handle some temperature swings. As for the clean beers, I do try to maintain as tight of control as possible...gotta make the best beer possible, right?

For what it's worth, I did try using air temperature instead of liquid temperature in the freezer for a while. My experience was that the compressor was constantly kicking on and off, even with a 3-4 degree differential. I felt it was too sensitive without that thermal mass of the beer to help regulate swings.

 

[Whsoj]

Sounds tricky. Is that something anyone can do? Or would I need to get someone with some knowledge to help me out.

Well I feel comfortable doing and I'm a DA. Your obviously not, realizing the density of the beer would hold temps longer and not cause as many cycles from the kompresser. That being said you could find a DIY somewhere I'm sure.

Also I don't know how much that big of a freezer costs but I'm pretty sure a new kompresser is cheaper. What will cost is r12 that crap is up to 50$ a pound! Find the A/C cert teacher at a local community college sometime the classes do it for parts! I replaced mine in 2006! still strong but mines for wild game

 

[sennister]

Well I feel comfortable doing and I'm a DA. Your obviously not, realizing the density of the beer would hold temps longer and not cause as many cycles from the kompresser. That being said you could find a DIY somewhere I'm sure.

Also I don't know how much that big of a freezer costs but I'm pretty sure a new kompresser is cheaper. What will cost is r12 that crap is up to 50$ a pound! Find the A/C cert teacher at a local community college sometime the classes do it for parts! I replaced mine in 2006! still strong but mines for wild game

Yeah it is true they can be fixed. There are some issues. While I am not a refrigeration tech I had one out at my house a while back to work on my Beverage Aire Keggerator when it wasn't cooling and we discussed many of these points. Mine is an older R12 unit. The diagnosis was either the startup relay (that ended up to be the issue in my case luckily as it is a cheap fix) or compressor and/or refrigerant. I looked at options for new compressors but unless I could find an R12 unit it made it more problematic. The good news was that I have a big tank of R12 that my father bought back before it was banned. If I couldn't locate a R12 compressor though that was sized right I would have to change refrigerant to one of the new standards. The problem with this is that they are not all compatible with each other. There is one that is supposed to work but he mentioned it isn't ideal and not as efficient as R12. I couldn't switch to a newer refrigerant easily because there would still be remnants of R12 in the system which would cause more issues. If it is refrigerant being low the problem is where did it go? You can fill it back up but if there is a leak it will just leak out again causing not only pollution but as mentioned @$50/ lb or whatever it costs now, an expensive temp fix. When researching the issue that I was having I learned quite a bit on how they work.

My thought is (again not a Ref Tech) that if you are getting ice build up on the outside of the unit, that it is chilling. That is good. If the coils on the unit are really dirty, it can't operate properly. In a house which is normally a lower dust environment compared to outside, you should be using a vacuum at least once a year to clean the coils. Hey I am just as guilty as probably everyone else and I know the fridge in our kitchen is 8 years old and it has never been done. I cleaned the coils on my Keggerator when he was out to work on it. I should do it again.

 

[sennister]

It does help quite a bit. Thank you. I do have other beers in the freezer at all times. I've currently got seven full carboys in it. 4 of those are sours, so they never move. They can handle some temperature swings. As for the clean beers, I do try to maintain as tight of control as possible...gotta make the best beer possible, right?

For what it's worth, I did try using air temperature instead of liquid temperature in the freezer for a while. My experience was that the compressor was constantly kicking on and off, even with a 3-4 degree differential. I felt it was too sensitive without that thermal mass of the beer to help regulate swings.

Where do you have the freezer? Garages can be hard on them. Up here they are typically way too cold unless you heat them and that will mess them up. You are in CA so maybe it is fighting high temps. Are the seals good on the door? You want to make it as insulated as possible. I would also get one of those meat probes with an extended cable. Try and run the T-stat in the air and monitor the liquid temp with the meat probe. They play with the differential to see how much of a swing you are getting. You said it was running a lot at 3-4 degree diff in air. You could probably go 10 degrees and still be fine. It all comes down to how tight of a control you want over the temp of the beer. If you are fine with 2-3 degree change in beer temp you could probably get by with 10-15 degree change in air temp depending on how well the unit is insulated and how long the time is between runs of the compressor. There are too many variables to say what you should set it at. More so if this is sitting in a garage where it may be 100 degrees one part of the year and 60 the other part of the year. If it is in a house it is more consistent so you can figure out what works for you and set it and forget it. Where in a more dynamic environment you may have to play with the differential more often.

I have a Johnson Controls T-stat running my Kegerator. I forget what I have the differential set at but it is around 6-8 degrees I think. I really should mount the probe somewhere in the fridge but it just sits near one of the kegs. I make sure to keep it away from a new keg though which is why I kind of like not having it in a fixed location. Once they all balance out in temp it doesn't matter as much.

 

[ICWiener]

The freezer is out in the garage, and yes, it's 100+ degrees in there during the day. It is cooling. Ice does build up on the inner front wall, so I know there's no leak. It's just starting to take longer to bring my beers to the desired temp. I know it's rough on the freezer out there, but I can't bring it into the house. It's like seven feet long! I do have a small space heater with a fan inside of the unit. It kicks on in the winter, especially at night, when the garage gets down into the low 40s.

I do like to maintain tight temperature control over my beers that are actively fermenting, especially early on. I would hope that most other experienced brewers out there would agree with me. I may let the temps swing a lot more for now, in order to extend the life of the freezer.

Who knows, I'll dig into the unit tonight...see what it looks like. With any luck, it's just a bunch of dirt.

 

[ICWiener]

Here's a picture...

 

[sennister]

The freezer is out in the garage, and yes, it's 100+ degrees in there during the day. It is cooling. Ice does build up on the inner front wall, so I know there's no leak. It's just starting to take longer to bring my beers to the desired temp. I know it's rough on the freezer out there, but I can't bring it into the house. It's like seven feet long! I do have a small space heater with a fan inside of the unit. It kicks on in the winter, especially at night, when the garage gets down into the low 40s.

I do like to maintain tight temperature control over my beers that are actively fermenting, especially early on. I would hope that most other experienced brewers out there would agree with me. I may let the temps swing a lot more for now, in order to extend the life of the freezer.

Who knows, I'll dig into the unit tonight...see what it looks like. With any luck, it's just a bunch of dirt.

I totally understand why it is in the garage but didn't want to assume. For all I know you have a big patio door on a walkout basement so it would be easy to get in the basement. If you even have one. I knew you said it was big.

If you have an air compressor with a blower attachment I would use that and a vac to try and clean up the coils. It is going to help. I understand that it is best to have a tight control over fermentation temp but you should also weigh the consequence. Burning up the compressor. They are going to struggle in extreme environments.

If you have one of those temp probes with remote display it would be interesting to use that to play with your differential setting like I mentioned. Because the environment the freezer is in will constantly be changing with the seasons you may find that it will impact how you want to configure it.

Also should it die in the end it may look at options where maybe you have two smaller unit so that it is possible to bring them inside where the environment isn't so harsh. Depending on how much room you have in your house of course. Or a custom built fermentation chamber. There isn't much to them and it would probably be more efficient to run.

 

[ICWiener]

If you have one of those temp probes with remote display it would be interesting to use that to play with your differential setting like I mentioned. Because the environment the freezer is in will constantly be changing with the seasons you may find that it will impact how you want to configure it.

I do. I've got a Ranco 2-stage controller hooked up. Maybe Summer time is going to have to be all about letting that internal temp go up and down a little more.

Also should it die in the end it may look at options where maybe you have two smaller unit so that it is possible to bring them inside where the environment isn't so harsh. Depending on how much room you have in your house of course. Or a custom built fermentation chamber.

Unfortunately, that's a no-can-do. 2 kids in a 3 bedroom house....

Honestly, my thought is that I should just modify the freezer shell. Utilize what I've already got to make a custom chamber. It's insulated, it's big, and it's paid for. I would just need to work out the details on how to cool it down.

 

[sennister]

Check out what this guy did. It looks like an option that might work should yours die. Basically use another fridge as the source to cool your freezer.

I would insulate the coolant lines but it looks easy enough to build.

http://www.youtube.com/watch?feature=player_embedded&v=3bb4VUleM5s

I am in the same boat with 2 kids and 3 bedroom house. We are fortunate to have a 2 car garage that we don't use that is pretty much underground so it stays cool in there. Then we have outbuildings where we park.

 

[ICWiener]

Check out what this guy did. It looks like an option that might work should yours die. Basically use another fridge as the source to cool your freezer.

I would insulate the coolant lines but it looks easy enough to build.

I thought about going the DIY route, but time is not a luxury in my world...plus I'm trying to keep replacement costs down. What I think I might do is just buy 2 chest freezers off of craigslist. They're cheap, I can hook them both up to the same temp controller, and I won't have to sacrifice fermenter space.

 

[sennister]

I thought about going the DIY route, but time is not a luxury in my world...plus I'm trying to keep replacement costs down. What I think I might do is just buy 2 chest freezers off of craigslist. They're cheap, I can hook them both up to the same temp controller, and I won't have to sacrifice fermenter space.

You could try that but even if you found two that were the same make, model and age, you may find that they cool at different rates. So if you were only using a single thermostat, you will likely have one that is warmer or colder than the other. The benefit of going with two though is one could be used for lagering and the other ales. I would splurge and get a second thermostat. They are not that much.

 

[ICWiener]

You could try that but even if you found two that were the same make, model and age, you may find that they cool at different rates. So if you were only using a single thermostat, you will likely have one that is warmer or colder than the other.

That thought crossed my mind pretty much right after typing my post. You're right, a second controller would be in order. Although, no lagering for this guy. I would most likely use it as a storage tank for sours. I just haven't found any lagers that I like enough to be worth the extra effort. Personal preference, I guess.

 

[Whsoj]

but ICWeiner you wouldn't happen to be a Futuama an?

 

[ICWiener]

HA! You betcha. Quite possibly the greatest television show ever created!

 

[Whsoj]

I believe the ic weiner joke is from the first episode I was glad they brought it back, sad to see it go agian. Edit: I just caught the Zap quote

 

[ICWiener]

Yeah, it's a recurring joke. They bring it out once a season or so.

I update my signature quote once every few months, but 9 times out of 10 it's a Zapp Brannigan quote. He really is the best.