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Keeping resevoir cool

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Howdy all.


I'm wondering if I can use a fridge as a resevoir chiller????


My plan is to run a copper coil through a fridge I ripped out of a caravan and pump water from the resevoir, through a long length of copper pipe and back to the resevoir....


Any ideas on if this would work???? And if it is worth a try where should I put the holes in the fridge??? In a few grows I'll be running a few more lights than usual in a room too small for them, but I can't afford the extra wattage of an air-conditioner to cool it down and the cost of water chiller's is ridiculous.


take care

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If your res is under 100L or so, then just freeze a couple of 2L coke bottles filled with water and then drop-em in. The ice will lower the temps quite well, or at least drop it the 2-5 degrees that makes the difference. Keep one in the tank, and one in the freezer and you should be right. Good idea about the fridge, but I have a feeling you'll prefer this method on cost.... ::D:
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yeah... hey I really like the idea of this one so I got a few thoughts I'd like to add... this sort of thing might take awhile to properly sort..hehe


I think you want only two holes in the fridge..one in and one out.. can you hire a high speed drill for cutting metal with?


about the fridge... I think you'd want an old one...really old.. like thirty years old... one of those ones where you open it and you can see the freezer box.


what you want to do is take out the freezer part of the fridge if you can.... I you can't then that's ok..


you want to wrap the copper pipe around the freezer box then put it back in the fridge.. also cut up lots of pieces of copper pipe and shape them so they fit nicely inside the freezer box. then connect the pipes using plastic stuff like food grade vynl pipe or something similar like silicone pipe etc... I wouldn't want to hold the pipe in place with screws or anything...use glue or silicone..hehe or make a box like feature that can slide in and out of the fridge... connected in such a way that maximum surface area touching the freezer box and enough inner pipe to support the whole thing...


then you can make little copper coils or whatever and put in the fridge space... or even use that vynl pipe, as copper could get expensive....


you might even need a cig welder for this stuff... and get a sparky to check... and get a safety switch for the fridge...I know someone who had a house fire cause of their fridge being faulty..


I was just thinking of a mate who has a freezer about the size and dimensions of a bar fridge...this could work wonders..hehe... no shitty little freezer box to work with and the door opens just like a normal fridge..hehe... or you could pick up an old second hand deep freezer...much better idea that one...

Edited by Mr Putard
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yeah, I was only gonna put in two holes and they would be fitted with lots of silicon so the fridge is still airtight.


As for the fridge, I've already got it. It is old, I dunno how old. I'll go have a look at it...... yeah, its an Electrolux gas/electric fridge out of a caravan. Its got one of them tiny little freezers that cant fit 2 cans of drink with cooling tubes in it. So I figure I can cut away all the freezer casing and leave the cooling tubes in the main part of the fridge.


I can drill the holes no trouble, But I dunno if there is anything in the outside of the fridge I should worry about. I figure I'll put the tube in thru the top and out thru the top.


It'll be cheap for me to do as I've already got the fridge, a decent pump 1000lph I dont use at all, tons of different tubing, etc.....


All I need to buy is the copper piping, so I guess I may as well give it a try. I'll probably go with the bits of copper connected by that soft clear tube. 'twas a great idea.


As for the water bottle idea luke, I've tried it before and it worked good, actually I used it to stress a crop to make some ultra white widow. (It was winter when I did it and just turned off Nutrient Heater and stressed the plants in the 36hr dark period. Probably didn't get peak potency out of them but the buds looked awesome, in a bag they looked totally white and not like a bag of pot.) but I dont wanna use the water bottle method as I'm planning on running a fair few lights in my small space. Gonna be an interesting grow I'm gonna use top, side and even bottom lighting, 1800w for 2 plants. So real experimental shit. I need a water cooler of some kind as I can't afford to run an air-conditioner.


I figure with the fridge my missus will be able to make some kind of formula so I can calculate what setting the fridge should be on and keep the temperatures fairly perfect. I could even hook a thermostat up to the pump if it works.


take care

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hey WC I don't think it will work. just gut feeling. I don't think it will be that effective in cooling grow area, and if it is, the fridge will struggle, because it will have nowhere near the capacity to cool an outside heat source. Know what I mean? Either way I think you're gonna be wasting your time.


You say you can't afford extra wattage for A/C, but how much power will that fridge suck? being an old fridge quite a bit I'm guessing. Personally I would look at getting a cheap 2nd hand car airconditioner from a wrecker or mechanic or something and rigging that up. Maybe if you can even swap your fridge for one :D Never done it myself but someone else mentioned on this site once that it worked well.

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Is the reservoir inside or out side the grow room? If inside would moving it out work, if outside have you ever seen one of those old camping fridges (Coolgardie?) where you have a tray at the top and hessian running from inside the tray and down the sides, you fill the tray with water and it siphons into the hessian where it evaporates and the area inside is kept cool?


If you need to use the fridge you could keep the reservoir outside it, run the feeder pipe into the fridge section and make a couple of loops in there and submerge them in a tub of water, the water will get chilled by the fridge and in turn cool the nutrients as they pass through, take care not to chill them too much or you could shock the plants.



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Yeah well basically I'm gonna go through with it, I've got everything I need to get for it except copper tube so It should be free. If I don't do it I'm gonna chuck the fridge anyway, but if it does work good (I'm pretty optomistic) I'll be laughing and spare alot of money.


As for cooling the grow area, I'm hoping I can keep that at outside temperature with a ton of venting, I'm planning on running over 2000m3 of exhaust so I figure there will be no time for any heat to get in. My main heat worry is the room that the growbox will be in, I can't vent it, and that is where the resevoir will be, but oh well. The heat isn't gonna be a killer on the plants but I will have some lights very close to my buckets which will heat the water like crazy, and I'm also gonna be running alot of wattage per square foot.


I liked your idea tom of keeping a container of water in the fridge, added that to my plans.


Anyway, here is my shitty diagram for the fridge, hopefully I will be able to post pictures of the thing if it works.


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As for the hessian bag idea (is that called ozmosis??) I feel it could only cool the resevoir a degree or two at most. I'm hoping my fridge idea will be able to compete with a real aquarium chiller and be run without my supervision and set to a thermostat to keep an even resevoir temperature.


Heres another shitty diagram of my other crazy idea, the setup with lights all around. Hoping for over a pound per plant.


Any more input on either of my 2 ideas????

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