Providing an overview of how you might set about comparing domestic downflow and upflow furnaces is a relatively straightforward process. The ‘flow’ of a domestic furnace actually refers to the path by which the heat is output from the furnace. A point which many people find surprising, as they automatically presume it will refer to the cold air flow into the furnace, in order to make the heat generated more or less intense.
3 Types of Domestic Furnace Flow
There are in fact three types of furnace flow, with the commonest ones being upflow and downflow.
An upflow furnace takes cold air in at the bottom of the furnace and discharges the heated air at the top. Conversely a downflow furnace will draw the cold air in at the top, with the heated air being vented from the bottom of the furnace.
You can also get a horizontal flow furnace, sometimes known as a cross-flow configuration furnace, where the furnace draws cold air in on one side and vents the hot air from the other.
Downflow or Upflow?
The direction in which the heated air is expelled from the furnace has a direct bearing on where the furnace is to be located. Needless to say, any domestic furnace needs to be able to be vented to the outside of a building and a horizontal flow furnace can be located pretty well anywhere in a property. However, to maximize the benefits of the heat coming out of downflow and upflow furnaces there are two specific locations that they should be placed in.
An upflow furnace pushing the heated air upwards should be located in a basement, so as to ensure the heat keeps on travelling upwards heating the floors of any rooms directly above it. Conversely a downflow furnace would be located in the attic, so that the heated air can most easily warm the rooms directly below.
If you were to reverse these two situations, a downflow furnace would be wasting heat, heating the basement floor; whilst the upflow heater would be wasting heated air on the external roof of your property.
Domestic Furnace Usage
A domestic, or house-hold, furnace is invariably used to provide heat and hot water throughout a home, rather than just being used to heat any one room. This is frequently achieved by using the heat generated to warm a reservoir or tank of water, the heated water is then pumped around the property to spread heat throughout the home by way of a hot water piping/radiator system.
At the same time the hot water can also be drawn from the reservoir for use in the domestic water system feeding to hot water faucets throughout the property. Some furnaces spread their heat throughout a property by allowing heated air to pass through conduits throughout the property.
Traditionally domestic furnaces would have been fueled by coal or wood. However, in many modern buildings, as such fuels require reasonably constant attention to keep them burning, modern domestic furnaces are tending to be fueled by LPG, fuel oil and gas.
The vast majority of properties that are suitable for having a domestic furnace will already have one, so people looking to buy a new domestic furnace are invariably looking to replace an existing furnace.
There are three major considerations for you when buying a new furnace. Making sure you by one that is the correct physical size to fit into the space where the existing one is, or a space that you want to move it to; that the furnace is an efficient one that won’t waste fuel or produce excessive emissions and, finally, that you pay the very best/lowest price possible.