What supplies do I need to install a furnace?
If you are installing an oil or gas furnace you will need added supplies to complete the installation. The piping that supplies the fuel to the furnace should include a manual shut-off outside of the unit. The high-voltage electric supplying the system should have a disconnect switch at or near the furnace. Properly sized flue piping from the furnace to the chimney will ensure a proper draft and fuel combustion. Make sure all the duct dimensions are the correct size for both the supply and return air. An undersized duct will cause the furnace to overheat and short cycle.
An oil-fired furnace will need to have its fuel and pump filters checked and/or replaced annually. This includes the fuel nozzle. An oil nozzle is rated by its spray type (hollow, solid, semi-solid), fuel rate (gph), and the degrees of the fuel spray. The oil pump pressure should be about 100 psi. The carbon dioxide (CO2) in the flue should be around 8%-12%. The smoke test should be 0-1. Stack temperatures will differ depending on the efficiency of the furnace.
Depending on the efficiency of a gas furnace, the flue can be made of steel or PVC. A high-efficiency, condensing, gas furnace with an AFUE of 90% or more will have schedule 40, PVC piping for its exhaust and fresh air return flues. Stack temperature for a condensing-flue furnace should be under 140°F. High-efficiency gas furnaces need to be maintained less than oil furnaces. Always keeping air filters clean and burners adjusted properly is the key to premature breakdowns and efficient operation.
