Checked unit out. per customer unit will switch from combi to hot air and show low water. Couldn't get unit to duplicate problem. Tested on steam mode twice and combi mode twice, no problems while checking, found pressure switch cutting in and out while unit was running not always showing pressure. Will order pressure switch and solenoid and return. 4/30/18 returned with parts removed pressure switch and one way valve & installed new pressure switch and one way valve. tested unit once parts were installed. Unit working better but still showing low water every so often when in combo mode or steam. Found loose connection on motor drive board and dirty water probe. Cleaned up and ran unit on combi and steam, all okay.