Earlier this past summer out home's HVAC system died, and was deemed not worth fixing due to it's age. We replaced it with a new 'dual fuel' setup, which is supposed to be the best / most cost effective setup for our climate w/ current tech... Basically a heat pump for AC and heat down to about 35*F, and a gas furnace for heat below that...
Saturday night was apparently the first night the temp got low enough to trigger the gas furnace, and Sunday the thermostat was showing error messages and we had no heat...
We didn't have the tech come out Sunday because we had to go down to CT for a family picnic (at about 60*F) at a state park that the GF's mother is very fond of.... It was supposed to have been earlier in the year, but we had to postpone because of the GF's father having some medical problems, (They are both in their 90's and not doing so great, albeit not bad for their age...)
Today the tech showed up and found that the tech who 'commissioned' the system had shut off the gas as part of his testing, and forgotten to turn it back on...


The system ran fine until it needed to call for the furnace, which naturally didn't run w/o gas, and the error it threw shut down everything... The tech turned the gas on, and tested the rest of the system to verify the fix, total time at our house about 30 minutes, much of which was just waiting for the system required 5 minutes between cycles...
Annoying but glad it was an easy fix...
WheelyCurious