68 degrees that is. The perfect temperature (give or take a few degrees) to brew that special ale. Here is a little ditty that you can construct which will give you a constant temperature for fermenting ales with very little maintenance required. The parts list is as follows:
1 - 10 gallon beverage type cooler
1 - 5 gallon beverage type cooler
1 - Johnson Control Thermostat
1 - Small submersible fountain type pump
2 - Plastic bucket spigots
2 - 3/4” GHT female connectors (cast brass type)
1 - Short section of 3/4” hose or tubing
1 - Short section of 3/4” A/C tubing insulation
1 - 3 to 5 ft section of 3/8” to 1/2” ID thick wall tubing (size to match pump fitting)
6 - 8” snap ties
The basic concept is that the fermenting beer in a 6.8 gal carboy goes in the 10 gal cooler and the pump goes in the 5 gallon cooler. The 5 gal cooler serves as a cold water reservoir. The water is cooled by placing pop bottles or milk cartons filled with frozen water in the cooler full of water on a daily basis or as required. The pump delivers cold water from the reservoir to the space between the outside of the carboy and the inside of the10 gal cooler on demand from the Johnson Control thermostat. The thermostat probe is placed in the 10 gal cooler. The cold water passes over and cools the carboy and then returns to the reservoir.
The coolers are connected at the base from the spigot holes with the plastic bucket spigots (modified), the GHT fittings and the short section of garden hose or tubing. Enlarge the holes as necessary to accommodate the fittings. Any equally ingenious plumbing arrangement which provides a water tight connection of the coolers at the base will suffice. The section of hose is insulated with the A/C tubing insulation which is held in place with the snap ties. The coolers must be set at the same elevation to maintain the same water level in both coolers. The water level inside the coolers should be about 3/4 of the depth of the carboy.
The 3/8” or 1/2” tubing (match the pump fitting) delivers the cold water from the pump in the reservoir to the side space in the 10 gal cooler. Thick wall tubing helps prevent kinking and provides a greater degree of insulation. You must drill holes in the lids of the coolers to accommodate the tubing from the supply pump, the power cord for the pump, the probe for the thermostat and the neck of the carboy. Use drills which match the outside diameter of the tubing to allow for a tight fit.
There is no way to explain all of the minor details with out a drawing. You are however, only limited by your own ingenuity. Do not hesitate to make changes and improvements that work. If you have been fermenting at room temperature, you have something to look foreword to. You will taste the difference.
Contributed by Joe Berryman