purchased for my mother in law who has breathing problems. after carefully following the instructions and setting it up i turned it on. it was very loud and within minutes was churning out thick smoke with a horrendous burning smell, the top was red hot and burning on the inside and was still really hot after unplugging it and leaving it for 30 minutes. This equipment is seriously dangerous if it had not been immediately turned off i have no doubt it would have caught fire. i hope this is a one off fault but would not reccomend this to anyone ever!!!!