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gill_za
Never Knows Best
I have finished assembling the cooler and placed the radiator into the lowest shelf where i keep all the utricularia (terrestrial and epiphytic). At the moment the cooler is set to "factory" thermostat setting. I am trying to see if this would be enough to cool the shelf down. The most obvious problem I forsee is the fact that the shelf is not completely isolated (although not for the lack of trying).
that hole where the tubing enters is now mostly closed.
The fan is currently set to 9V.
The humidifier that is plugged in into the same shelf
Cooler itself
Temperature after the pump was started jumped from 45F to 57F.
Im am not home right now. But while i was there the temperature in the tank climbed all the way to 63F. The temperature in the shelf dropped from 81F to 78F while the thermometer was close to the raditor. I have moved the thermometer further away before leaving and will check on it later.
that hole where the tubing enters is now mostly closed.
The fan is currently set to 9V.
The humidifier that is plugged in into the same shelf
Cooler itself
Temperature after the pump was started jumped from 45F to 57F.
Im am not home right now. But while i was there the temperature in the tank climbed all the way to 63F. The temperature in the shelf dropped from 81F to 78F while the thermometer was close to the raditor. I have moved the thermometer further away before leaving and will check on it later.
Heli
villosaholic
gill_za
Never Knows Best
well if the shelf gradualy cools down to 77 with light on, i won't need to lower the thermostat setting. Also, i need to see if the night temperature drops to lower 60 or high 50.
with lowest thermostat setting water starts to freeze. Anyway, more observation is needed. Right before I left the radiator started to condense moisture like mad.
I forgot to mention. Im using 10' of ID 1/2 copper tubing on the return line. In addition the pump was switched from 100gph to 200gph. I may switch the fan to 12V later. Right now all the fans are plugged into the same adjustable 12V 2.5A power supply and are set to 9V.
@Heli,
Nope, I returned it to the settings that it was on when I got the cooler. But with the pump on so far the cooler hasn't turned off for 2 hours...
with lowest thermostat setting water starts to freeze. Anyway, more observation is needed. Right before I left the radiator started to condense moisture like mad.
I forgot to mention. Im using 10' of ID 1/2 copper tubing on the return line. In addition the pump was switched from 100gph to 200gph. I may switch the fan to 12V later. Right now all the fans are plugged into the same adjustable 12V 2.5A power supply and are set to 9V.
@Heli,
Nope, I returned it to the settings that it was on when I got the cooler. But with the pump on so far the cooler hasn't turned off for 2 hours...
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Hey Gill_za
I noticed the same thing with my cooler. It couldn't keep up with the heat dissipation of the radiator. Once the pump turned on the water temp would rise and the compressor would run all day trying to catch up. You should try sealing the top off with some sort of insulation. Also the shorter the tubes, the better it will be. If anything else, add coolant and turn that baby all the way down.
I noticed the same thing with my cooler. It couldn't keep up with the heat dissipation of the radiator. Once the pump turned on the water temp would rise and the compressor would run all day trying to catch up. You should try sealing the top off with some sort of insulation. Also the shorter the tubes, the better it will be. If anything else, add coolant and turn that baby all the way down.
gill_za
Never Knows Best
At this point the cooler's compresor has reached its peak capacity. Even if I turn the thermostat all the way down it will unfortunately not help me lower the temperature of the coolant because the compressor is working non stop anyway. Thermostat only tells the compressor to stop when a certain temperature is reached, but if that temperature is not reached (as in my case) it will just continue working. Too much heat bleeds in into the shelf and is transfered into the coolers tank. Compressor is just too weak to compensate, you are right.
I gave up on cooling the shelf and have just removed the radiator from the shelf (flooding the floor around in the process). It is now installed in an empty 55G aquarium with the top sealed (reflective bubblewrap).
So far
temperature inside the aquarium is: 64F
temperature in the room is 78F
temperature of the water in the tank is 56F.
I am going to wait and see if the difference between the room temperature and tanks temperature will increase. In addition I'm planning on ordering this: http://www.newegg.com/Product/Product.aspx?Item=N82E16835185054 to increase the heat transfer rate and perhaps wrap the tank with reflective bubblewrap. If all this fails I will start thinking about alternatives (or smaller tank).
Thank you.
P.S.: Just checked
Room temp: 80F
Aquarium temp 60F
Water temp NA
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TheFury
Oh, the humanity!!
Hey y'all - so with summer pretty much in full swing, I've noticed the same thing as you. My tank stays right around 78F during the day and can get down to 62-65 at night with my cooler running and the Peltier helping it out. But it runs pretty much constantly overnight now.
On Monday (which was hot as hell up here in the Northeast) my cooling rig was actually running non-stop all day trying to keep temps down. Temperatures maxed at about 80F while my Hygrotherm is set to kick on at 77F... kind of concerning. But considering that it was approaching 90F in the room and that I've got four hot T5HOs running above the completely enclosed terrarium, I'll call that a win.
If my terrarium were any bigger I'd be up a creek! I'm also glad that all of my Neps in my terrarium are either intermediate or intermediate/HL hybrids. If I had splurged on a pricy UHL Nep it might have croaked by now!
On Monday (which was hot as hell up here in the Northeast) my cooling rig was actually running non-stop all day trying to keep temps down. Temperatures maxed at about 80F while my Hygrotherm is set to kick on at 77F... kind of concerning. But considering that it was approaching 90F in the room and that I've got four hot T5HOs running above the completely enclosed terrarium, I'll call that a win.
If my terrarium were any bigger I'd be up a creek! I'm also glad that all of my Neps in my terrarium are either intermediate or intermediate/HL hybrids. If I had splurged on a pricy UHL Nep it might have croaked by now!
gill_za
Never Knows Best
Quick check this morning:
Placed the 200gph pump into a 1gal aquarium (without tubing of-course, so it would be circuiting the water inside it) and about 10 minutes later saw no change in the temperature.
I've been following this with great interest, and strictly from an engineering point of view.....
I would assume that the compressor and condenser coil (Which has to remove the heat from the system) have been sized based on providing cold drinking water (short, intermittent use)
Asking it to do much more than that would be a stretch..... the engineers would have selected the components based on the design application cost effectiveness with some (but not much) "service factor" overdesign. You have to design a product to do a job and do it as cheaply as possible in order to be competitive or you fail.
Just my 2 cents.... I dont want to rain on anyone's parade and it may work great. However, commonly accepted design philosophy would cause me to wonder for how long if so. I would imagine your high side pressures are excessive due to excessive system loading.
You might try adding addtional airflow to the condenser coil.
I would assume that the compressor and condenser coil (Which has to remove the heat from the system) have been sized based on providing cold drinking water (short, intermittent use)
Asking it to do much more than that would be a stretch..... the engineers would have selected the components based on the design application cost effectiveness with some (but not much) "service factor" overdesign. You have to design a product to do a job and do it as cheaply as possible in order to be competitive or you fail.
Just my 2 cents.... I dont want to rain on anyone's parade and it may work great. However, commonly accepted design philosophy would cause me to wonder for how long if so. I would imagine your high side pressures are excessive due to excessive system loading.
You might try adding addtional airflow to the condenser coil.
Butch, I'd have to agree with you. This is by no means the ideal system but its a cheap way that works for smaller gorw areas. If I had the money, I'd spend it on an aquarium/hydroponic water chiller capable of some serious cooling.
I think I will try setting a fan to blow across the condenser coil in back. Its completely exposed and perhaps I could even set the back of the cooler near to my window AC unit to get cold air right on it.
I think I will try setting a fan to blow across the condenser coil in back. Its completely exposed and perhaps I could even set the back of the cooler near to my window AC unit to get cold air right on it.
gill_za
Never Knows Best
I have also thought about using that lower compartment that is a little refrigirator for additional cooling. I'm thinking of putting a copper coil in there and run output water through it before reaching the radiator. Although I turned that refrigerators' thermostat to off it is still cooling. Both the water cooler and the refrigerator use the same compressor after all.
In addition I have installed the 120mm fan onto the condenser in the back right across the compartment with the compressor to pull the hot air away from both. I may try and use my bigger honeywell fan to cool the condenser coils as well.
In addition I have installed the 120mm fan onto the condenser in the back right across the compartment with the compressor to pull the hot air away from both. I may try and use my bigger honeywell fan to cool the condenser coils as well.
gill_za
Never Knows Best
So for now I have added a 15' copper coil into the lower refrigerator compartment of the water cooler I have. The water from the water cooler gets pumped out and passes through the coils in the refrigerator on its way to the radiator for additional cooling. The returning water from the radiator passes through a 10' cooper coil that is placed in the water cooler itself. Unfortunately I can only get 10F difference (in this thread the thermometer was too close to the radiator) in the temperature (with no additional external heating source such as lights). I have noticed however that there is still some heat I could shed in the bottom refrigerator as the temperature even with coil inside stays at 50F while the temperature in the top water cooler is 65F, 67F with 80F in the room.
av8tor1, I was wondering does it mater which line I'm running through the bottom cooler at this point, to_the_radiator or from_the_radiator? I'm still putting the same load on the system?
Three possible improvements to squeeze more juice out of the system that I see so far are:
1) Obviously I need to insulate the tank.
2) Run both to_the_radiator and from_the_radiator lines through the bottom refrigerator
3) Increase the length of the copper coils placed in the radiator.
Pardon the mess, this is work in progress
Cooler
I took off the door for now and instead paced that slab of styrofoam. Wasn't ready to drill the door just yet.
Puuling the hot air from the compressor compartment:
Copper coil in the water cooler:
av8tor1, I was wondering does it mater which line I'm running through the bottom cooler at this point, to_the_radiator or from_the_radiator? I'm still putting the same load on the system?
Three possible improvements to squeeze more juice out of the system that I see so far are:
1) Obviously I need to insulate the tank.
2) Run both to_the_radiator and from_the_radiator lines through the bottom refrigerator
3) Increase the length of the copper coils placed in the radiator.
Pardon the mess, this is work in progress
Cooler
I took off the door for now and instead paced that slab of styrofoam. Wasn't ready to drill the door just yet.
Puuling the hot air from the compressor compartment:
Copper coil in the water cooler:
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Gill, Im not sure it answers your quesiton but....
When it comes to heat exchangers you usually want to counter flow..... in other words heat transfer is proportional to temperature differential. You want the hottest part of region "A" to be in contact with the coldest part of region "B" for highest energy transfer.
On thing i would look at is the copper tubing, that is very inefficient..... the only transfer going on is the small liquid boundary layer that is in contact with the copper. This is why most heat exhangers have multiple "flattened" passages instead of a singular tubular passage.
I would think another heater core/heat exhanger or (rolls eyes lol) "rad" would be a better alternative to a few coils of copper tubing, but that is just an educated guesstimate.
http://en.wikipedia.org/wiki/Heat_exchanger
When it comes to heat exchangers you usually want to counter flow..... in other words heat transfer is proportional to temperature differential. You want the hottest part of region "A" to be in contact with the coldest part of region "B" for highest energy transfer.
On thing i would look at is the copper tubing, that is very inefficient..... the only transfer going on is the small liquid boundary layer that is in contact with the copper. This is why most heat exhangers have multiple "flattened" passages instead of a singular tubular passage.
I would think another heater core/heat exhanger or (rolls eyes lol) "rad" would be a better alternative to a few coils of copper tubing, but that is just an educated guesstimate.
http://en.wikipedia.org/wiki/Heat_exchanger
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gill_za
Never Knows Best
Av8tor1,
Thank you! It makes perfect sense actually. I was thinking along the same lines yesterday imagining the flow of heat like the flow of air from the high pressure areas to low pressure areas. The bigger the difference in pressure the stronger the flow
As it happens I have another heat exchanger lying around. So would you recommend sticking it into he reservoir with water and just pump returning warmer water through it (instead of the coils that are there now), or perhaps putting it into the refrigerator compartment, attaching a fan and running it this way instead?
Flattening the coils... hmm knowing myself Ill probably mess up and block it accidentally. I'll try that as well.
Thank you!
Thank you! It makes perfect sense actually. I was thinking along the same lines yesterday imagining the flow of heat like the flow of air from the high pressure areas to low pressure areas. The bigger the difference in pressure the stronger the flow
As it happens I have another heat exchanger lying around. So would you recommend sticking it into he reservoir with water and just pump returning warmer water through it (instead of the coils that are there now), or perhaps putting it into the refrigerator compartment, attaching a fan and running it this way instead?
Flattening the coils... hmm knowing myself Ill probably mess up and block it accidentally. I'll try that as well.
Thank you!
