How to Install a Furnace

Installing a new or replacement furnace is not a job for the average homeowner or DIY enthusiast. Furnace installation requires skills in the form of electrical, plumbing (gas) and sheet metal work. It may, however, help many homeowners to understand the process of furnace installation. For more skilled "do it yourself" homeowners it is possible to install a replacement furnace but this is highly dependant on the skills of the homeowner. Someone that has had considerable experience in construction and skilled trades can undertake the job themselves. It is very important that this installer does have the skills required and follows all safety precautions.

This article is intended to be a guide for swapping a similar new furnace and not for converting from gas to electric or visa versa. A change in the type of furnace being used is a much more complex procedure. HVAC training is usually a certificate or Associates Degree equivalent with several years of industry experience. HVAC professionals are also usually licensed by the state or area where there are working.

Before beginning any repair or replacement project be sure to turn off all electric and gas supplies. Double check this.

Furnace removal:

Once all power and fuel to the unit has been turned off, it is time to remove the old unit. This is really a two person operation. Gas and/or electric supplies to the old furnace must be disconnected. The thermostat wires need to be disconnected as well. Next, the ductwork and vent piping must be removed. Sheet metal can have very sharp edges and must be handled carefully. If the furnace is connected to a central air-conditioning system this will need to be removed as well. Refrigerant handling does require a special license in almost all areas. Remove all screws that attach the furnace to the mounting base. Once all parts have been disconnected the old furnace can be removed from the area.

Installing the new furnace:

Each type of furnace will have a different type of installation procedure. At this point in the replacement, a manual is required for the exact installation of the furnace involved. In general, the area of installation needs to be clean and free of debris. The new furnace must be set level on the mounting base. The blower motor must be installed if not already in the unit. Duct work and venting must be reconnected. Thermostat wires must be reconnected as well as other electrical and gas lines, if used.

After installation:

Once the furnace is set and all gas, electrical and refrigerant connections have been made, testing of the system is required. All ductwork and venting must be sealed for leaks. If the furnace is a gas system it is critical to check for gas leaks. A furnace system that is connected to central air must be checked for refrigerant leaks. Combustion analysis should be preformed as well as tests on oxygen, carbon monoxide and carbon dioxide. Special equipment is required for these tests.

Again, this is only a quick guide to what is involved in furnace replacement. Hopefully from understanding the process of furnace installation the homeowner can be more comfortable with their furnace and how it is installed. For the homeowner that contracts the job, or performs the installation themselves, it is important to remember that most building codes will require the inspection of the final installation. This is not done to be an annoyance but as a safety measure. Leaking gas, improper venting or substandard electrical work can be extremely dangerous. Hopefully from reading this you will find that the cost of professional installation far outweighs the savings of doing it yourself and the dangers involved.

References:

http://www.alpinehomeair.com/heating/how%20to%20buy%20a%20home%20heating%20system.pdf
http://www.wisegeek.com/what-should-i-know-about-furnace-installation.htm
http://www.furnacecompare.com/furnaces/installation.htmlhttp://www.citytowninfo.com/employment/hvac-mechanics


Disclaimer:
"There are no federal or state laws that prohibit a homeowner from purchasing and installing a furnace in his own home. Unless your local municipality has laws that state otherwise, legally you can buy and install your own heating system, provided you get local permits and install the product according to manufacturer and building codes. However, you cannot service or install heating equipment in another person's home unless you are licensed to do so, which is regulated by your state or City."
From:
http://www.alpinehomeair.com/heating/how%20to%20buy%20a%20home%20heating%20system.pdf