... bulb is 20C, wet bulb is 15C, and inlet water temp 15C, outlet water temp 55C. Test conditons:2.Low: Air source side inlet ... bulb is 7C, wet bulb is 6C, and inlet water temp 10C, outlet water temp 55C. 3.Super low: Air source side inlet dry ... bulb is -15C, wet bulb is -17C, and inlet water temp 10C, outlet water temp 55C. EVI air to water heat pump for low temperature