Safe furnace installation includes testing for gasoline leaks, confirming correct vent slope
https://telegra.ph/Canadian-Heating-and-Air-Conditionings-Checklist-for-Moving-Into-a-Home-with-a-New-Furnace-01-19
Safe furnace set up includes checking out for gasoline leaks, confirming accurate vent slope, and making sure ok combustion air for secure winter warmness.