Whether you are trying to buy after market furnace parts, Carrier furnace parts, Goodman furnace parts, Trane furnace parts, or oil furnace parts to do routine maintenance like replacing filters or a major repair, there are a few guidelines you should follow. You will need to check your warranty first, and then have the year, as well as the complete make and model number of the furnace handy, what type of fuel it uses, and know which part you need.
Look to see if your furnace is still under warranty, in which case, this repair might be covered, and you just need to call the repairman. If it is still under warranty, but this repair is not covered, all work may still have to be performed by a licensed repairman or you may be able to do it yourself, but you would have to use the name brand parts for your furnace. Using after market or refurbished parts could void your warranty. Also, if you have the papers describing the furnace, they may include a diagram of the furnace with a list of the parts giving you the part numbers, which can be very helpful.
The internet is a very good place to look for the parts dealer or parts you need and some of them will even give you step by step instructions and/or a live person to call or instant message with questions. Ordering parts either from a catalog or online can become expensive when the shipping costs are added in. If you do not have readily available internet access, there may be a number to call on the papers you got with your furnace, or you can check the yellow pages for a parts dealer in your area. Taking the old part in and getting the new one on the spot is faster and more foolproof; however, this is not always an option.
The regular maintenance of your furnace is extremely important for the best fuel economy and heating efficiency. They recommend you change the furnace filters every season for that as well as preventing future problems to the blowers or motors, and a faulty thermostat can lead to costly repairs at a later date. You may want to buy filters to keep on hand, so you have them when you need them.
When buying any furnace parts, you will want to check the return policy. This can vary greatly depending on not only the dealer, but also the part.