Learn about Downflow / Horizontal

ManualsBrandsGoodman Manualsforced air96% 40,000 BTU Downflow/Horizontal Furnace

4) Installation

Doing It Yourself

If you’re someone who does

his own home mechanical

projects, such as plumbing,

electrical or carpentry, you

might be able to do some or

most of your own installation.

If you’re interested in how to install a furnace, there are

four areas of consideration for you to contemplate:

Legal

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, pro-

vided 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.

Most towns and cities require one or more permit(s) to be

obtained when installing a new heating system or replacing an

existing one. The purpose of obtaining a permit is so that your

local building authorities can inspect your project if they wish

to make sure it was done according to national mechanical,

electrical and gas piping code (published standards for how a

proper installation should be done).

Obtaining a permit usually involves calling your city permit

department, giving them your address and specications for

the heater you’re installing, and sometimes making a payment.

If you need permits, the three types are mechanical, electrical

and plumbing (plumbing permit for the gas piping). Permits

range from no cost to $50 each on average. Call you local city

permit department for details and costs for your area.

Safety

The most important consideration regarding how to install a

furnace is making sure it is done correctly and safely for the

home’s occupants. The two greatest potential hazards from

improper installation are leaking vent piping or leaking fuel

piping. This can occur due to improper materials, wrong or no

sealants used, or loose connections.

The potential hazard of a leaking vent (chimney) pipe is that

if the furnace has incomplete combustion (caused by a dirty

furnace that needs cleaning or a tune-up) then carbon monox-

ide will form and be vented into the home through the leaking

pipe. Carbon monoxide is an invisible odorless gas that when

breathed blocks oxygen from entering the blood and within a

short period of time will cause poisoning and death. Each year

about 80 people in the US die from carbon monoxide poisoning.

The other potential major hazard could come from a fuel

pipe leak, whether it is gas, propane or oil. If there is a large

enough fuel leak and an open flame or spark is nearby, an

explosion will occur. The result could be a massive catastro-

phe that would demolish the home and almost certainly kill

any occupants in it at the time. Needless to say, a very major

problem.

Other hazards that need to be taken seriously are:

Electrocution from mishandling or improperly wiring high •

voltage lines

Fire caused by improper wiring or improperly sized break-•

ers/fuses

Fire caused by improper clearances from combustibles•

Cuts from mishandling sheet metal•

Damage to property due to leaking water from improper •

installation of certain units

This isn’t an exhaustive list of hazards or everything you need

to know to be safe. The standards for how to install a furnace

are outlined in the manufacturer’s installation instructions

included with the product (see example here).

Practical

Next, consider the practical aspects of installing it yourself:

Skill Level –• Do you know how to do these types of mechani-

cal projects? Installing a furnace is similar to installing a mod-

ern water heater. It involves skills from the plumbing, electri-

cal and sheet metal trades. If you have experience with such,

you might consider doing some of this work yourself. If you

don’t have experience with such, now would not be a good

time to learn. Due to the above mentioned safety concerns it

is strongly recommended that you perform your own furnace

installation only if you have experience in these skills.

Tools – • Assuming you have the skill level, do you have the

basic tools required?

Time –• Do you have the time to do this yourself? Replacing

an existing forced air furnace, boiler or packaged unit will

take an amateur about one to two days, depending on the

home and installer skill level.