A Little Disappointed. First day, Oct. 31st, the oxygen concentrator was delivered. The manager went over everything with me thoroughly. The machine worked fine when he left the house. At 10:00 p.m. I proceeded to prepare for bed. Turned the machine on. It cycled like it was suppose too and then top red light and beeper noise began. I repeatedly done this 4 times plus hit re-set button. We call the 1-800# thinking some one could walk me through the process to make sure I wasn't overlooking something as this is all new to me. Was told some one would contact me soon. At 2:00 a.m. he called. Now He is suppose to be here before noon today, Saturday, Nov. 1st. Glad It wasn't life threatening. Karen Dunn, Plainville Client.