Post by RuBisCO on Feb 18, 2017 23:28:40 GMT -5
I thought I would post here on a little project that I have been working on. I have been feeling bad for the heliamphora that I acquired last fall as they have been in inadequate conditions (although doing ok). I have been able to slowly piece together a more comfortable highland setup for them. I was going to post this in the 'how cool are your plants' thread but I couldn't seem to get the photo link to work.
I was toying around with peltier units in series and got my 18x18x36 exoterra down to 17C (without lights on) - not very good all-in-all so I moved on to a different method that I thought I would share.
This is a pretty simple and effective way of providing cooling with a pretty small footprint and overall investment.
I decommissioned the dehumidifier that was running in the basement for a 'higher' purpose so-to-speak.
The dehumidifier basically has a cooling radiator just like a refrigerator and it will effectively cool a bucket of water to ice if left running submerged. Taking the panel off and pulling the front 'cold' radiator out I dropped it into a bucket of water. The copper tube bends easily by hand and the panel was just held in place by a plastic bracket that was easy to remove.
When it is plugged in and normally operating as a dehumidifier it is controlled by a humidistat, but for this application it required modification. I wanted to be able to control it with a timer, which meant bypassing the humidistat control to be able to turn it on and off simply by applying 120V power. If I left it on 24/7 it would just turn my bucket of water to a solid block of ice, so I wanted to run it on a timer to get the reservoir of water to a cold but non-freezing temperature. Running this particular setup for about 30 minutes will already form ice around the submerged components of the radiator coil. This process required probing with a multimeter to find the right way to hotwire a couple of relay switches. Now it can be turned on an off by a simple timer and I have a good supply of cold water to use as coolant.
I have it on a timer to basically maintain a temperature of the reservoir around 10Cwhich means it runs for 15 minutes every hour and a half or so. There is a pump that sends coolant through a 240mmx120mm CPU cooling radiator that is on the inside of the tank. The tank is not insulated, nor is the bucket of water/coolant.
So with this setup I keep the coolant pump running 24/7, the 'dehumidifier' runs as indicated about 15 minutes every hour and a half or so.
Daytime temps with a bank of 8x24inch T5 lights directly on top of the glass lid with mylar wrap around the three sides are easily kept at 19-20C.
Nighttime temps are a comfortable 12-13C with lights off.
I am sure that if I kept the cooler, or added another radiator/pump in the terrarium that it could get lower temps.
I have a little homemade 24V fogger on a float in a small reservoir that serves to provide humidity (bottom left of the tank, not easily seen). I am going to work on improving the humidity control in the future as I am maxing out at ~75% nighttime and ~65% daytime humidity with the current setup. I can certainly seal the tank a little better in a number of areas so this shouldn't be a problem. This fogger is on 24/7 as well.
Anyhow, I am looking forward to getting my heliamphora and seedling highland neps into their proper environment.
I am still going to tinker with peltier cooling with CPU cooling setups but I don't think it would hack the large tank. Maybe another post will follow but it is hard to find the time to tinker these days.
Hope this is helpful for those who might be exploring different options for highland setups.
Cheers!
I was toying around with peltier units in series and got my 18x18x36 exoterra down to 17C (without lights on) - not very good all-in-all so I moved on to a different method that I thought I would share.
This is a pretty simple and effective way of providing cooling with a pretty small footprint and overall investment.
I decommissioned the dehumidifier that was running in the basement for a 'higher' purpose so-to-speak.
The dehumidifier basically has a cooling radiator just like a refrigerator and it will effectively cool a bucket of water to ice if left running submerged. Taking the panel off and pulling the front 'cold' radiator out I dropped it into a bucket of water. The copper tube bends easily by hand and the panel was just held in place by a plastic bracket that was easy to remove.
When it is plugged in and normally operating as a dehumidifier it is controlled by a humidistat, but for this application it required modification. I wanted to be able to control it with a timer, which meant bypassing the humidistat control to be able to turn it on and off simply by applying 120V power. If I left it on 24/7 it would just turn my bucket of water to a solid block of ice, so I wanted to run it on a timer to get the reservoir of water to a cold but non-freezing temperature. Running this particular setup for about 30 minutes will already form ice around the submerged components of the radiator coil. This process required probing with a multimeter to find the right way to hotwire a couple of relay switches. Now it can be turned on an off by a simple timer and I have a good supply of cold water to use as coolant.
I have it on a timer to basically maintain a temperature of the reservoir around 10Cwhich means it runs for 15 minutes every hour and a half or so. There is a pump that sends coolant through a 240mmx120mm CPU cooling radiator that is on the inside of the tank. The tank is not insulated, nor is the bucket of water/coolant.
So with this setup I keep the coolant pump running 24/7, the 'dehumidifier' runs as indicated about 15 minutes every hour and a half or so.
Daytime temps with a bank of 8x24inch T5 lights directly on top of the glass lid with mylar wrap around the three sides are easily kept at 19-20C.
Nighttime temps are a comfortable 12-13C with lights off.
I am sure that if I kept the cooler, or added another radiator/pump in the terrarium that it could get lower temps.
I have a little homemade 24V fogger on a float in a small reservoir that serves to provide humidity (bottom left of the tank, not easily seen). I am going to work on improving the humidity control in the future as I am maxing out at ~75% nighttime and ~65% daytime humidity with the current setup. I can certainly seal the tank a little better in a number of areas so this shouldn't be a problem. This fogger is on 24/7 as well.
Anyhow, I am looking forward to getting my heliamphora and seedling highland neps into their proper environment.
I am still going to tinker with peltier cooling with CPU cooling setups but I don't think it would hack the large tank. Maybe another post will follow but it is hard to find the time to tinker these days.
Hope this is helpful for those who might be exploring different options for highland setups.
Cheers!