A Bit Confused.....

Well, I guess I shouldnt' be....this is Texas....BUT, the heater folks came out to the house today to look at the heater that isn't working. (Which wouldn't be a big deal except that is has been dropping down in the low 40's at night.) They looked at it and figured out what the problem is. "It was too cold outside for the heater to work."
Yep! That was their explanation. Apparently "these heating systems weren't designed to work when the temperature is below 35 degees."
OH!!! My mistake....silly me, I thought that is when you are supposed to use it. HA! What on earth was I thinking?