My Next Project

[PistolPatch]

[For those reading this for the first time, it's probably best to ignore most of the below as the original idea has changed dramatically! Sometimes, it's nice to see silly ideas become less silly! The latest idea was posted on 28th March - Post #15 below.]

Have been working on designing a system that will enable the fermenting, cold conditioning and dispensing of lager and ale using my existing converted freezer.

My plan is as per the diagram below...

The main fridge is a converted 360litre freezer which sits at 2 degrees.

Above this I would like to make a cold cabinet built from coolroom panel.

I intend connecting the cabinet to the fridge with insulated 70mm PVC, joining hole A to other hole A and joining hole C to other hole C.

The cold cabinet will be divided in two and by hole B.

Each hole will be covered with a circle of foam on metal attached via a single screw as in the figure below enabling the holes to be completely or partially open/closed.

I only really have to open the main fridge a few times a week, if that, and am hoping that the excellent insulation will enable me to adjust the holes to provide the 10 and 18 degree temps in the cabinet above very simply through convection. (I am hoping to avoid the use of fans, controllers etc.

A pics of my existing fridge can be found here...

Link

Have no space to connect the primary ale fermenter to this system so will just keep using 100 Can Cooler and ice bricks for this.

If I can brew both ales (for the freeloaders) and brilliant dark lagers (for me) in a one bedroom apartment, Ill be absolutely wrapped!

I would really appreciate any feedback on this. E.g. Will it obviously NOT work??? Is 6wks from ferment to keg enough for the lager etc. etc.

 

[stephen]

Pistol

Looking at your design I think you may have to look at fans and temp controllers. The area you live in is predominantly warm-hot so convection will most probably not work. Hot air rises and cold air sinks!

Jaycar has a simple kit for about $20.00 (Cat No. KA-1732 - in the 2003 catalogue) that can be used to control a computer fan (again around $15-20) that will operate from a 12v supply. The kit is quite simple to build and wiring the fans in is quite simple. The 12V supply can be sourced from an old computer.

I would suggest having two seperate setups for your lager and ale compartments - ie. one set at 10 deg and the other at 18 deg with their own inlet an outlet ports. The ports would only have to be 50 mm to accomodate a 50 mm fan. I would also place a fan inside your fridge just to circulate the air. This could work out to about an $80-100 investment. The ports could made straight through the roof of your fridge.

I'm sure you will get other ideas from others and if I could use a computer I could use your diagram to demonstrate what I'm trying to say: Just use four lots of A's across the roof.

Steve

Disclaimer: If you are not comfortable with electrical/electronics then seek the assistance of someone who is.

 

[PistolPatch]

Thanks Steve! You've made the fan bit sound a lot easier than I thought. Thanks also for the part numbers. I was hoping that with Hole C being higher than Hole A I would have got some sort of convection but as you say I'm probably dreaming!

Back to work today so you've given me something to think on while I'm out in the heat. Thanks again mate!

P.S. Saw your other post about the hair - lol!

 

[Boots]

Pistol
I'm in the process of sourcing a chest freezer, and like you, was planning on making it multitask.

I was thinking of something similar, but as stephen has already said, i was going to use computer case fans in the piping.

I was also thinking of sheathing the main pipe work with a larger pvc pipe for extra insulation as in my plan the pipework would all be external to the cooled sections. Could then stuff the cavity between the two with insulation / expanding foam if necessary.

Keep us updated on how you go, and good luck.

 

[PistolPatch]

Thanks for your reply Boots. This thread was getting lonely!

For the insulation I was going to use flexible black pipe insulating foam as it works well and isn't too expensive for the amount needed. The expanding foam's a great insulator though it can be a bit messy to work with (used some just the other day!) and is about $15 a can though you should only need one.

I went to the coolroom shop but alas they buy in all their coolrooms so will have a hunt around somewhere else for panels when I get some more time.

To satisfy my enquiring mind, I thought I'd build the setup first without fans just to see what can be done. Don't worry though, when I see how dismally it works, I have a fan ready to go. :lol: Maybe though the info will be of use for some other application - you never know!

Have you thought of an upright freezer? I'm wrapped in mine as I can get 6x23litres in it and it has a small footprint. People say that you lose the cold air when you open the door, which is true but if you're only using it for kegs and have an outside gas bottle and tap, you really only need to open it a few times a week, if that. And you can put stuff on top of it!

Anyway, Boots, thanks again and I'll let you know when I get somewhere with this. PP :beerbang:

P.S. I think the big worry for us is going to be drilling 50mm holes without hitting any internal organs of the fridge!

 

[Screwtop]

Just a thought boys, fans create airflow, correct? Then where you position the fans would be immatesticle in a static space. ie: you could not suck air from one box without having an opening to allow air into that space for airflow and vicky versa for the other space. Have you designed these things so that air is continuously circulating from the temp controlled space through the non temp controlled space and back again. A fan moving air in one tube in one direction and the other tube used for return of air in the other direction (it too could have a fan, but probably would not increase effeciency). Just my 2CW.

Edit: Typo spelled continuously the Kiwi way contunuously

 

[Asher]

My first ever fermenter box was an insulated box that sucked air from a fridge with a return line back to the fridge....
eventually it worked well, but ended up costing allot more than another old fridge... But I must admit I had fun tinkering with it at the time so money was till well spent IMO...

This talk if using computer fans is all good, but you'll find they don't particularly like sucking or blowing down tubes very well & the motor is in-line so adds heat to the system anyway... After several attempts I stumbled on a 12volt air mattress blower-upper.... You can connect it to the black insulation piping (I used this stuff as piping on its own) outside the cooling area too. And fan speed is adjustable by getting an adjustable voltage source.... they work a treat. I had mine sucking/blowing through about a meter of pipe and had the voltage set at 9 on a cheap plug in DC source from dick smiths that could be switched between 3/6/9/12V....

O'h yeah... If your only using one fan and relying on air pressure to force air back to the fridge the whole system will need to be airtight

Asher for now

edit: spelling

 

[fifteenbeerslater]

Good one ASHER,sounds like you did the same as me but i got away with the PC type fan, my tube length was only 100mm long. I am now building a Coolroom with a section for fermenting as well.
Cheers15BL :beer:

 

[PistolPatch]

Thanks for the input Screwtop, Asher and 15!. In the interests of science, homebrewing and generally mucking around (like Asher, the tinkering gives me a buzz!) I'll first attempt getting my cool box to 18-20 degrees without fans.

This will be a nice first step for me and may be of benefit down the track for ale brewers at least! I'd be wrapped as well if I can manage to acheive just that. I'll have no partition in the top box to start and will just cut holes A to A and C to C. Of course, the lower the C going into the fridge the better the convection but I suppose someone has to explore!

Might take me a few weeks to get all this sorted but will keep you posted on the temperature results of this project/my fantasy!

I wonder if anyone knows if you can safely drill through the back or top of a fridge? Drilling through fridges I find a little unnerving especially when we're talking 50-70mm holes. More research!

Cheers and thanks! :beer:

 

[stephen]

Pistol

Drilling through fridges/freezers is dependant on the make, model, year etc. A lot of old fridges and freezers had or have a cooling plate/box etc readily visible in the inside of the sooling compartment. These are readily identifiable after time as they generally tend to frost up a bit/lot and genarally have a dimple aluminium look. With these type cooling appliances the plumbing is quite simple. They will have (most often) a black grid/mesh assembly located at the rear of the appliance. This is called the condensor. If this the case the plumbing is (generally speaking) easily traced as where it enters the cooling compartment will be a direct line to the evaporater (the cooling part inside the fridge) and where it exits to the evaporator.

Now, if all of this is located at the rear of the appliance and all the refridgerant plumbing is easily traced as entering and exiting the fridge from the rear ( as a lot of cooling appliances are - generally speaking) then you can be fairly confident that there is no cooling pipes in the walls or roof of your appliance.

If you are unable to locate any of these pipes then do not tamper with your appliance without seeking profesional advice. Some of the newer cooling appliances utilise the inner skin as the evaporater and have the refridgerant plumbing all over the place. However, if your chosen appliance is older than about 10-15 years old then all your plumbing should be at the rear of the appliance and therefore the sides and roof are good to go.

Disclaimer: This is an generalisation and no particular model was discussed. If you are in any doubt then seek the assitance from a proffssional.

(I am not a profesional!!! Just a tinkerer)

 

[stephen]

Referring to what I was talking about above. If you look at the photo below the goldy coloured bit of metal that is either side of the inside of the fridge at the top is the item I was referrring to as the evaporator. This one has a freezer built into it but should have the inlet and outlet plumbing to the rear.

Steve

PS Thank you to Finite for the photo.

 

[Screwtop]

Stephen do they still use bundy tubes in the cabinets to reduce condensation around door seals. That would be about the only piping that would run internally in the side walls. These days almost all control connections run externally (within the cooler cabinet) in plastic duct.

 

[PistolPatch]

Hey Steve, thanks for the detailed reply - pretty damn good for a tinkerer! What you've written has made me feel a lot safer in the drilling department.

I have the condenser on the back. Inside the freezer, about two thirds of the way down at the back behind a plastic cover is a silver pipe about 1cm in diameter. This snakes from side to side about five times and is joined by fins. It's probably 60cm wide by 30cm high. I always thought that this might have been the defrost mechanism (my fridge is a converted freezer) but after reading your post I suppose this is actually the cooling mechanism and the fan at the top of the cabinet is the defrosting mechanism. (You can see I know a heap about fridges! lol)

I'm thinking now that going through the top will be pretty good with no heat loss. If I extend the Hole C into the cool box with a bit of PVC, this may create enough convection to at least get the cool box to 18. As I said before though, I may just be dreaming here!

Thanks again Steve!

 

[PistolPatch]

Oh! And Screwtop, I was just re-reading this thread and I should have mentioned that my plan was that warmer air from the fridge would flow up into the cabinet through Hole C, then find its way through Hole B and then back into the fridge via Hole A. As I've said above, I'm probably dreaming that this could even remotely work without a fan but I'm going to enjoy seeing what happens! lol!

Maybe I can get the whole cabinet to 10 degrees without a fan. Now that would be great as well! Enough of my ramblings! Cheers mate!

 

[PistolPatch]

I think I may have a new idea to solve the above problem at last! I have just purchased a 65litre Esky Ice King on Wheels. ((Please excuse the shocking picture quality - camera phone!)



By turning it on its end, I can get a fermenter in it as follows.



The next problem is maintaining temperature. Heres my latest idea which uses your existing fridge, a $20 aquarium pump and a $5 timer.



The esky has a drain plug which is at the base of the esky when it is sitting in the, fermenting fridge, position (i.e. as you see it sitting on the fridge above). The drain plug undoes leaving a 20mm hole. All I intend to do is drill a 20mm hole through the top of my fridge and then set up as in the following diagram.



The pump sucks from its base and so will be attached to the cold back wall of the fridge. The pump does not give off any noticeable heat. (Just ran it in the esky for an hour and temp went up not even 0.5 degrees.) Not sure how much pump will like living in the fridge though.

Ill also work out some sort of soft foam to put around the 20mm pipe for further insulation.

My aim is to pull the wort down to fermenting temperature using freezer blocks in the esky. One this is reached, I am confident that the aquarium pump will maintain either 9 or 18 degrees just be altering the timer. (I actually scored 2 of these timers for $8 in total so Im hoping to use one as an ale timer and the other as a lager timer.)

I cannot do a brew for 2 weeks, so I am going to start experimenting with pulling down and maintaining temps during this time. All I need now is a digital thermometer with a 0.5m flexible probe. I better start searching. Mind you, if someone has an instant answer on the probe, Id appreciate it, as I want to start testing asap.

So, now I can get all my brewing gear in one tidy spot!...



Further uses of the esky can be found in All In 1 Esky/Mash Tun/Fridge/Party Cooler

Credits: The idea was triggered by a picture Fingerlickin posted of a carboy lying down in an esky. I have no idea what made me think of putting the esky on its end. Pretty simple really! Also, thanks to all above who took the original idea (and me) seriously! You all know me now though!!!

 

[MVZOOM]

PP - I love your enthusiasm! :beer:

Can I suggest, before cutting anything, that you may well be able to achieve a very constant 18deg with just a couple of icepacks? Ie.. change / revolve them daily and you really shouldn't have an issue.

The sheer volume of the wort means that temp changes are not quick, it takes a lot of time to drop or gain 2-3 degrees and if it's in an insulated esky (we;ve all had ice left over after 1.5 days in an esky, right?), it really won't be a problem. Also, the fact that it's a nice tight fit means that you're not dealing with cooling a large amount of dormant air.

Correct me if I'm wrong, but even 10 degrees should be do-able.

Sure, prob a bit of work, but it's 5mins each day? Otherwise - great thinking!

Cheers- Mike

 

[delboy]

THERMOMETER-FRIDG-FISH TANK-OFFICE-AIR-CONDITIONING ST2 Item number: 7604739308

pp goto ebay enter this item no don is realy help full and rocks :beerbang: ,
tell him uss-kittyhawk sent you

delboy

 

[PistolPatch]

MVZOOM: - I am appalled by your totally sensible suggestion. Your good advice means that I cannot get my drill out for several more days or perhaps ever! What a dissapointment!

I am quite frightened that, as you say, the, "the fact that it's a nice tight fit means that you're not dealing with cooling a large amount of dormant air," and therfore, the simple act of buying an esky without the far more exciting modifications that I proposeed will suffice, (I'm so hoping you are wrong - LOL!)

I did run this idea by a few others before posting here and one comment was...

"You may find that the 100 can cooler will get you to lager temps by using more iceblocks."

I replied, "Unfortunately no. I have about 10 large freezer blocks (plus a few small ones) and even with 3 rotations a day of 3 blocks, on some days, Im battling to keep 18. In fact, now I just hope for 20. FYI, the main problem with using so many freezer blocks is that, up here, with the humidity, the constant opening and closing of your freezer means that youd be looking at defrosting every fortnight. I imagine this would not be a problem with self-defrosting freezers."

So Zoom, I will do some intital tests, (I can start them tomorrow thanks to you - cool!) before I drill any holes! Seriously, thanks for the heads up.

Hold on! I think I may yet get to drill my holes! Smaller space, more rotations, impossible for me to maintain! Great!

Either way, it looks as though testing can start tomorrow!

P.S. Delboy - thanks for the info. I'll have a look there in detail tomorrow and let you know how I go.

 

[MVZOOM]

Heh, heh - good stuff.

Now, wish you were close enough for me to enjoy the fruits of your labour! :chug:

Cheers - Mike

 

[PistolPatch]

Cheers Zoom. Am just racing out the door for a 12 hour bucks party but have just put 23 litres of 30 degreee water in the 'fermenting fridge' with 5 large freezer blocks. Unfortuantely that's all I could fit in. (Another excuse to start drilling though!) I'll see what the temp changes to whenever I get home, if capable! At least that will give some sort of starting point.

Ken - will have to call you tomorrow due to the above. Look forward to your advice though. Thanks mate.