The Step-down 60W transformer that powers the 12v/ac lights in my garden fountain needs replacement, as it now shuts down only a few minutes after being turned on. The transformer has built-in overload shut-off, and the total wattage of the lamps I'm using is 55W, just under the maximum. All connections checked out OK. So I purchased a 75W unit, thinking that it would better handle my 55 watts of light. The new transformer needs to be hard wired and will be inside a water-tight junction box near the fountain, and the 120AC runs from there through a conduit for about 15 feet, where it plugs in to a GFCI outlet. Would a transformer of this small capacity generate enough heat to require ventilation that this junction box doesn't supply? If so, any recommendations or consideration as to alternate place to mount it, considering this a "wet location")? Also any tips on hard wiring the 120v side of the new unit (to the existing insulated wiring inside the conduit, which powered the original transformer)???