Having gotten back into the darkroom after a 10+ year hiatus I remembered my frustration with getting water at a specific temperature for the developer. Not so much of a problem during the winter, but summertime temperatures coming out of the tap caused me to get a tub of water and toss ice in until I got the temperature I desired.
The results are a 2 gallon reservoir of water held at any desired temperature.
Components are a 2 gallon water jug with a dispensing spout and a fish tank chiller from amazon.
I then used my laser engraver to cut a new lid from some 1/4" acrylic sheet. I then 3D printed three pieces to keep the lid located on the top of the jug. I had decided the screw on lid would be a PITA and threw it away. One of the locating bits had holes for plastic tubing. I also created a fitting for a fill hole.
The 3D parts were printed in PETG which can be solvent welded to the acrylic sheet. two thin wall 5/16" OD tubes were pressed through the bulkhead. This was laid on top of the jug. a small fish tank pump sits in the bottom of the jug and the temperature sensor for the chiller is tie wrapped to the cord.
The pump circulates water through the chiller and them returns it to the jug. The controls on the chiller allow retaining the temperature to 0.1 degree. If the water gets too cold the chiller reverses polarity on the thermo electric units to heat the water.
The chiller turns off the fans and TEC modules when the water is the correct temperature. In effect the unit could be left turned on 24/7. The chiller will only cycle on for a minute or so every 15-20 minutes during my observations so far.
The unit will bring the water to temp in 15 minutes or so based on the starting temperature.
The results are a 2 gallon reservoir of water held at any desired temperature.
Components are a 2 gallon water jug with a dispensing spout and a fish tank chiller from amazon.
I then used my laser engraver to cut a new lid from some 1/4" acrylic sheet. I then 3D printed three pieces to keep the lid located on the top of the jug. I had decided the screw on lid would be a PITA and threw it away. One of the locating bits had holes for plastic tubing. I also created a fitting for a fill hole.
The 3D parts were printed in PETG which can be solvent welded to the acrylic sheet. two thin wall 5/16" OD tubes were pressed through the bulkhead. This was laid on top of the jug. a small fish tank pump sits in the bottom of the jug and the temperature sensor for the chiller is tie wrapped to the cord.
The pump circulates water through the chiller and them returns it to the jug. The controls on the chiller allow retaining the temperature to 0.1 degree. If the water gets too cold the chiller reverses polarity on the thermo electric units to heat the water.
The chiller turns off the fans and TEC modules when the water is the correct temperature. In effect the unit could be left turned on 24/7. The chiller will only cycle on for a minute or so every 15-20 minutes during my observations so far.
The unit will bring the water to temp in 15 minutes or so based on the starting temperature.
