We turned the sand on today. It gained 5F in just one sunny day. The last week, the lows have been near freezing and the trees are starting to turn colors. Last year we did not turn the sand on until late October which was too late. I think other years mid October has worked better, so we may overheat the house and turn the sand back off. (See Day 10 of house construction for a picture of the sand.)
Usually, before turning the house heat on we consult the temperature trends from our data collection system, but a bunch of our temperature sensors were out of commission. The sand and slab sensors failed a month and a half ago during a storm. Then the rest of the temperature monitoring system went during a lightning strike that also took out the transformer at the street. For now, Tyson soldered together two sensors for the sand and slab. One other sensor survived — upstairs air temperature.
This year we have had an alarming number of close lightning strikes. Through the various storms, we lost the DSL modem, a smoke alarm, Ethernet switch, Ethernet port on a computer, and the one wire hub and sensors.