The XT humidifier with an outdoor enclosure is offered for all single-cylinder XT models (002-048) for up to 143 lb/hr (65 kg/h). The XT humidifier with outdoor enclosure has NEMA 3R rated enclosure with operating temperature range between 40°F (5°C) and 120°F (50°C). An optional heating package with a thermostatically controlled heater lowers the operating range to -40°F (-40°C). Enclosure panels are fabricated from 14 and 18-gauge G-90 galvanized steel for corrosion resistance with weather-tight silicone sealant.