Gas furnace parts are available for sale online at vendors such as RepairClinic, Reliable Parts and Sears PartsDirect. All three vendors offer parts from popular furnace brands such as Coleman, Goodman and Lennox.
RepairClinic has a 365-day return policy on all parts. Customers have the ability to search for part by common furnace problem.
Reliable Parts offers flat-rate shipping for $9.95 as of 2015. Specific parts sold include gas ignitors, gas valves and ignition controls.
Sears PartsDirect additionally offers downloadable manuals and diagrams to help customers searching for the correct parts. Customers also search for parts by part number or furnace model number.