Learn about Downflow / Horizontal

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Consider Air Conditioning
If you already have central air conditioning currently, there is
likely no reason why you couldn’t continue to use it with your
new heating system. Regardless of dierences in brands be-
tween your new furnace and your existing air conditioner, they
will likely be compatible if you decide to keep you existing air
conditioner.
But if you are thinking of getting air conditioning or upgrad-
ing to a new one, now is a good time for that consideration.
Buying it at the same time as your heating system has advan-
tages. Firstly, since only some types of heating systems can be
coupled with air conditioning, now would be the time to make
sure your heater is compatible with a cooling system. All central
air conditioning systems are a “forced air” system, meaning the
air is blown through ductwork throughout the home. If you
want to have central air, then make sure to choose a forced air
heating system as your heating type as well. For example, if you
were deciding between installing a boiler or a gas forced air
furnace to heat your home, you’d want to choose the forced air
furnace since it will work with and support central air condi-
tioning, where as the boiler won’t. If you have a boiler, you can
still have air conditioning in your home, but you will need to
purchase an air handler unit for the indoors, and install ducting
in the home in order to have central air conditioning.
One of the main components of a central air conditioning sys-
tem is the evaporator coil. This is a type of radiator that installs
directly next to your forced air furnace into the duct system (it
might look like part of the furnace or ductwork when installed).
If you install the evaporator coil at the same time you install the
furnace, the evaporator coil installation will be fast and simple.
If you install the furnace and then later decide to add the evap-
orator coil, it will require the ducting to be reworked, which will
increase your air conditioning installation costs if you are hiring
a professional to do it for you.
Replacement or new installation
If you are replacing an existing heater system, equipment
swap-out will be a faster and easier installation than if installing
a new heating system in a new home or renovated property.
If you replacing an existing gas forced air furnace, you will
connect the furnace to your existing ductwork. A sheet metal
transition kit can make the job easier to connect the existing
ductwork to the new furnace.
If you are installing a new boiler, new hot water piping and
radiators will need to be installed throughout the home. If you
are installing the more common heater, the forced air furnace,
you will need to install a duct distribution system to carry the
air throughout the home. The same ductwork is used for both
your heating and cooling system, if you have cooling.
Ductwork
Ducts are the passageways that transfer the air throughout
the home. A duct system has two main duct types, called the
supply air and return air ducts. Supply air ducts are all the ducts
that are connected to the furnace that blow the air from the
furnace to the rooms. The return air ducts are all the ducts that
pull the air from the rooms back to the furnace. When a furnace
is operating, it is both blowing air to the rooms and pulling the
air from the rooms back to the furnace at the same time. As
much air as is blown from the furnace is being drawn back to it.
You can design and install your own duct system if you are
handy and want to save quite a bit of money compared to hav-
ing a professional
install it for you.
Designing a duct
system is relatively
simple to do when
you know how to
do so. There are two
primary things to
know:
You need to have return air ducting that can provide the 1
same air ow back to the furnace as the supply air ducting is
blowing out.
Your system’s total air volume has to be enough to supply 2
adequate air ow for your furnace (and air conditioning if you
have it). Keep in mind that the most common duct design
problem is too little air ow caused by ducting that is too
small, or because there are simply not enough ducts. This
causes equipment performance and maintenance problems.
Ask a professional for advice and it will quickly speed up your
design time learning curve.