exchangenergy VI serves Vancouver Island’s communities and is a recognized Carrier dealer.
Air source heat pumps have become one of the most popular heating technologies in North America. They are more than twice as efficient as the best fuel burning systems in existence. Rather than buying fuel from a utility, they extract heat from the air. They have become more efficient and much quieter in the past few years.
New developments are allowing them to become more efficient yet, especially at lower outdoor temperatures, which has been their weakness in the past. New models are now available to supply hot water for radiant floors as well.
“Forced air” is the most popular way to distribute heating and cooling via air source heat pumps to homes in North America.
In residential air source heat pump applications there are 2 different ways to use forced air: low velocity or “standard” systems and high velocity systems. High velocity systems were originally developed for retrofit cooling applications in the American southeast. Their use has grown now to more applications, the best example being where there are architectural restraints to installing conventional large ductwork.
Most forced air systems rely on one thermostat for the entire house. This means that great care must be taken by the installer to size the system ductwork according to the loads of each room.
Forced air can be zoned, but needs to be done by an experienced designer/installer. Zoning forced air is beneficial for energy saving and individual room temperature control.
Fresh air is easily incorporated into to forced air heat pump systems. Commercial and residential buildings require a certain amount of fresh air per person. If a building uses an alternative to forced air, an HRV should be considered as the preferred option.
Forced air systems work with air source as well as ground source heat pumps, or with furnaces which can be gas, oil, electric or wood fired, to name the most popular.
As mentioned previously, high velocity is a newer way to distribute air. Not that it has just been invented, but that it has recently been improved. High velocity systems use much smaller ducts then low velocity, or “standard” systems. Because of this, high velocity is common when a client wants to save head room in a basement, or in a retro fit application. High velocity systems push air out of the outlets at over 1000 fpm. This means a few things. The first is that high velocity outlets should be situated in corners of rooms and other locations where they will not disturb the occupants. No one likes air blowing on their head. The 1000 fpm has some other benefits as well. Air moving past 1000 fpm is self aspirating. This means that air will circulate itself. This in mind, it makes an installation easier than low velocity because you can use a central return air. Low velocity relies on return air ducts throughout the house to circulate the air. High velocity, being self aspirating, can function with one central return.
Most forced air systems installed in North America use low velocity. Costs are lower, and more manufactures support low velocity systems, which usually consist of large rectangular ducts, running the length of the house. From there, smaller round ducts are run directly to each room. In most residential cases, low velocity is an economical and easy way to go.
Heat recovery ventilators are an energy efficient “breath of fresh air”. HRVs recover the heat energy in the exhaust air, and transfer it to fresh air as it enters the building. The stale air is exhausted outside, and clean filtered fresh air is brought in. HRVs help your house breathe, and they are helpful for allergies and healthy living. Our Eneready HRV’s use as much power as two 50 watt light bulbs and will replace the bath fans in your house