Forced-Air Heating System
More than 70 percent of America's homes are heated by forced-air heating. With this type of system, room air is pulled into a furnace through large return-air ducts. The furnace warms the air and then sends it back to rooms throughout the house through a different set of ducts and registers.
Forced-air heating systems are very popular, but if not professionally installed they can be noisy and inefficient. The typical average in the nation shows that a HVAC system only delivers about 57% of the equipment's rated capacity, with professional adjustments this can be greatly increased.
High Efficiency furnaces that are rated above 90% AFUE use a secondary heat exchanger to extract heat from the exhausted flue gas which would normally be wasted to the outside. By extracting this heat from the flue gas furnaces are able to achieve over 96% AFUE rated efficiency.
Small Duct High Velocity
A High Velocity Small-Duct systems offers greater flexibility and improved comfort over conventional systems. High velocity systems move air at a faster rate which causes the air to mix resulting in even temperature throughout the house. Another advantage of the high velocity systems is that they remove 30% more moisture in the summer increasing comfort.
The high velocity small duct systems such as those produced by Unico and Spacepak offer greater flexibility in tighter spaces. The high velocity small-duct systems utilize an 8" round trunk duct with 3" flexible round duct as the branches which make it an ideal solution to new additions and basements where fitting standard duct work might be a problem.
High Velocity also have the advantage of offering a more even distribution of temperature to the room by throwing the air into the room at a faster rate it causes the air in the room to mix instead of stratifying in temperature layers with conventional systems. Rather than directly using gas heat exchanger as a heat source, high velocity systems rely on a hot water heating coil usually powered by boiler.