In the middle of a cold 20 degree night, with fresh snow and icy roads, our heat cut off without and notice of a problem. We called the emergency number and within minutes, the on call technician returned our call and headed our way. It was 1:15am in the morning and he showed up at 1:45. He took care of the problem and heat was back on in no time. It ended up being a problem with the humidifier that caused all of the problem.