DIY Chiller

[Kenji80]

Hi timebomb,

Can I know the wattage of your freezer?

Thanks.

[timebomb]

I'm sorry. I would like to know the wattage too but the specs on the freezer are all worn out.

Loh K L

[s050399b]

btw, how come the images are not displayed?

[zmzfam]

btw, how come the images are not displayed?

Did you read the replies in the thread you created ? http://www.killies.com/forum/viewtopic.php?t=1410

Refer to these two threads : http://www.killies.com/forum/viewtopic.php?t=1287 , http://www.killies.com/forum/viewtopic.php?t=1291

We prefer that you signed off with your real name, unless you're hiding from something. Also, do not expect to be spoon fed all the time as you have already been told to read through the FAQ/Technical Help sub-forum.

I just hope that the threads above will help solve your problem, as no other information was given.

[whuntley]

To change directions back toward the original subject, thought to share this with you:

I recently visited my local thrift shop (used stuff is donated and the proceeds go to charity) and I passed up a bar refrigerator that would have made a great chiller. Price? US$8.00!

I lusted for it, but had to admit that I had no place to put it that made any sense. Instead I bought a full size (18 cu ft.) frost-free refrigerator/freezer (that works) for $12. That one will replace the smaller one I have been using that has a broken temp. control. I have lost more than $12 worth of food because of the unreliable regulation.

Maybe I can use the old one to keep blackworms and other live foods out in my fishroom-to-be. Once unloaded and defrosted (the new one is frost free) I may be able to repair the control.

Do you have thrift shops like this in SG? Here folks get a deduction of income for donations to reduce their taxes, and the stuff sold is often very cheap.

I love the thrifts because they have soup bowls and other small ceramics that make great spawning containers, and I (once in a while) get a great deal on an aquarium. I picked up a 3G bow front with internal filter and hood for a couple of bucks, the other day. A 20G (12"X24"X18" high) was US$10 including a fluorescent hood and air pump, a couple of months ago.

No need for a chiller here, now. My fire went out this PM, so my fishroom was down to 20C. I received a bunch of Het. formosa and Endler's from B. G. Granier last week, but it was too cold for the Endler's on the way. The adults arived DOA and the two babies born en-route kicked the bucket, yesterday.

Wright

[aquafans]

Hi Loh K L,

Talking about drilling the cover, in the first page, I see that James' chiller use refridgerator not freezer and make a hole at the top.

Since I already have unused refridgerator and want to make a DIY Chiller, can you tell me how to drill it? does it need a special tool?, I have talked with people and they all said that its difficult to drill the refridge since it has 3 layers.

Thanks

[timebomb]

Since I already have unused refridgerator and want to make a DIY Chiller, can you tell me how to drill it? does it need a special tool?, I have talked with people and they all said that its difficult to drill the refridge since it has 3 layers.

The special tool you need is a drill, of course. It's used for drilling holes .

If you're drilling through the top, you will hit a piece of styrofoam sandwiched between the 2 sides of the fridge. The trick is not to drill right through. First, core a hole on the top. You should then be able to see the styrofoam. Use a small drill bit to drill through this piece of styrofoam until it makes a mark on the other side. This is so you know where to core from the other side. After having core 2 holes on each side of the cover, you then squeezed your hose through the styrofoam. This way, there's no leak and the fridge will still be perfectly insulated.

If, by any chance, you decide to make holes on the sides of the fridge instead, take note that there are coils. If you puncture a coil, the fridge will not work anymore.

Loh K L

[timebomb]

Do you have thrift shops like this in SG? Here folks get a deduction of income for donations to reduce their taxes, and the stuff sold is often very cheap.

We don't have thrift shops, Wright.

Over here, when people don't want stuff anymore, they sell it to the guy known as a "karang guni", the rags and bone man. He in turn exports the stuff to our neighbouring countries like Indonesia.

I wonder if "thrift shops" would ever work in Singapore. The closest thing we have to a "thrift shop" would probably be "Cash Converters", a shop that sells second-hand products.

Loh K L

[whuntley]

Do you have thrift shops like this in SG? Here folks get a deduction of income for donations to reduce their taxes, and the stuff sold is often very cheap.

We don't have thrift shops, Wright.

Over here, when people don't want stuff anymore, they sell it to the guy known as a "karang guni", the rags and bone man. He in turn exports the stuff to our neighbouring countries like Indonesia.

I wonder if "thrift shops" would ever work in Singapore. The closest thing we have to a "thrift shop" would probably be "Cash Converters", a shop that sells second-hand products.

Loh K L

This may well be a culture thing, too. I noticed the Japanese want nothing to do with a used item, and the folks in the US got great deals on replaced auto engines, as a result. Many such traits seem to be widespread across eastern asia. I wonder if this is one of them?

Our culture is a bit schitzo on this. We may prize antiques, but want a new car that costs twice what a year-old one sells for.

I'm not proud. I stopped by the thrift shop on my way home from our Tues. hike, this AM. Recent rains made the road very muddy and I wanted high-top hiking boots. I found a nearly-new pair, in my size, for only US$3. New, the same boots would have been over $100, I suspect.

Now, back to your regularly scheduled thread...

Wright

[RonWill]

Kwek Leong, there are thrift shops albeit not everywhere. I help out at the Church's thrift shop and am also a regular patron.

Crockery, clothing, household items, books and other bric bracs going for a song. I've seen 2ft tanks going for $5, terra cotta pots for 50cents, letter racks for $1, etc. and... urm... what was this thread about? :wink:

Back to those holes... "aquafans" (what's your name?)

There are powered drill attachments that has either fixed or multi-sized cutters which will first bore the pilot hole, followed by the final diameter of choice.

I love holes... check here for my 'Hole Cutter' page.

[aquafans]

Thanks Loh K L and Ronnie

KL, when you drill the inner side of refridge, did you laydown the refridge, is it ok to laydown it ?

Hole cutters, thats what I need, I guess its wood type drill, right?
I plan to do this project next week, so I have to buy everything before they close during Idul Fitri.

Jan.

[whuntley]

It is considered a generally bad idea to turn a refrigerator on its side. I'm not certain why, but have been told that liquid refrigerant can run into the wrong part of the loop and greatly reduce the efficiency. Makes sense to me.

Wright

[RonWill]

Jan,
These hole-cutters will work for acrylic, plexiglass and wood. It may cut through thin metal but I can't be sure.

I try not to DIY stuffs involving metal as these are more difficult to cut and finish, without resorting to expensive machinery or lots of elbow grease.

Good luck with your project and do update us along the way with pics, ya?

[aquafans]

Hi all, I've done with the DIY chiller project.


Specs:
- Minibar refrigerator, consume 75 watt
- 15 mtr water hose
- water come from powerhead inside the aquarium
- small fan (modified from kids toy)
- Temperature in aquarium is 25.x, before is 27.x (400 ltr)
- Temperature in chiller is 24.5



I'm expecting to get 22C in chiller, I think the system does not work effective, The ice compartment is frozen while water in hose container is 24c, its only a few centimetres between them, the ice even thicker before I use small fan (I though the wind will unfrozen the evaporator, but it is not). Whats in my mind is take off the evaporator plat and put it in the hose container, will it help? Any other suggestion?
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[aquafans]

I saw again the james' chiller photo, the thermal plate that laid below the hose actually is evaporator, thats why we dont see ice compartment.

I will need an expert to do this

[timebomb]

I will need an expert to do this

I'm not sure of this but only in certain brands of bar fridges, the thermal plate (evaporator) can be moved. In others, it's stuck to the fridge itself so there's no way you can take it out and position it under your hose.

But if you're already getting 25 C for your 400 litre tank, I would say you have already done well. Believe me, any colder and you will have to deal with condensation all the time. I run my DIY chiller such that it is switched off 6 hours a day. If it run it 24 hours non-stop, the condensation is so heavy I can't see my plants.

Loh K L

[TyroneGenade]

Hi Loh

I've had this thought in my head for some time and I can't get rid of it by normal thought experiment testing so here goes:

1) Your freezer can only remove so much heat per s (lets say 2W/s)

2) Your tank is shedding, say 4 W/s, and this rate is proportional to the surface area of the emmitter (the hose).

So, you are putting 4W/s into the chiller bag and the freezer is taking 2 W/s away.

3) But the rate of heat transfer is proportional to the difference in heat between the source and the sink.

So the heat sink (FZ) , chiller bag (CB) , hose (H) and tank (FT) eventually reach an steady-state where where the chiler bag can't absorb more heat till the freezer takes it away:

environment -> FT <=> H <=> CB -> FZ

Assuming that there is a direct correlation between heat loss and surfact area reducing the lenght of the your hose by half will mean your tank will shed 2W/s which is the same pace as what your freezer takes the heat away. This will force a new steady-state with more heat being taken from the tank. It will mean that the tank will initially gain some heat but should over time revert to a lower temp than before provided that the ambient room doesn't put more heat into the tank than the freezer can remove.

I think you need to get te knife out and experiment.

Start by removing 1/4 of the hose and see what happens. If it doesn't work then you can get a hose connector and put it back on.

Keep well

[timebomb]

.Start by removing 1/4 of the hose and see what happens. If it doesn't work then you can get a hose connector and put it back on.

Tyrone, are you saying if I reduce the length of my hoses, the temperature in my fish tank will become lower? Well, that's not hard to do. In fact, I can do much better than that. Besides shortening the hoses, I can also remove my other Eheim cannister filter from the system. Currently, I'm using 2 Eheims, one is running while the other is not. The water passes through the 2nd Eheim before it returns to the tank.

I'll go about it this weekend and report the results. Actually, I'm quite happy with 24 C but I wouldn't mind seeing 22 C for once.

Loh K L

[TyroneGenade]

What I am saying, is that if you reduce the length of hose in the chiller bag the freezer will be able to remove more heat creating a better heat sink.

The problem is that the chiller bag have already removed all the heat it can by the time the water has passed through 50% of the hose... A lot of experimentation will be need to find the optimum length. I'm sure a physicist could work it out for us but we don't have.:-(

Your 2nd Eheim may be an aditional heat gain for the tank but I can't see it being significant. Plastic is a good insulator... It has very poor heat transfer properties and air isn't much better.

What was the length of hose used for your friend's bar fridge chiller? and the tank volume? By chance he may of hit on just the right hose length.

Kind regards

[timebomb]

What I am saying, is that if you reduce the length of hose in the chiller bag the freezer will be able to remove more heat creating a better heat sink.

How can it be, Tyrone? Common sense dictates that the longer it takes for the water from the fish tank to pass through the chiller bag, the colder my tank will become. You sure there's nothing wrong with your formula?

I have to say I'm sceptical that your suggestion will work. I want a second opinion If someone else says your idea is worth a try, I'll reduce the length of the hose by a quarter. And then if it works, I'll reduce it by another quarter.

What was the length of hose used for your friend's bar fridge chiller? and the tank volume? By chance he may of hit on just the right hose length.

I don't think he's that lucky His hose, as far as I know is just as long as mine. He's using a whole roll bought from the same hardware shop. It's 50 metres.

Loh K L