A customer service complaint that new homebuyers often make is that the air-conditioning heats or cools various rooms throughout the house differently. Homebuyers telephone the builder or write-in customer service requests complaining that the second floor master bedroom is nice and warm (winter season) but the first-floor living room is always cold.
The reason for differential temperatures throughout the interior of the structure is that conditioned air travels different lengths from the furnace or the condenser…and if all of the wall registers throughout the house have their baffles opened wide…quantities of warm or cold air (depending on the season) will exit these registers in unequal amounts due to varying air pressures…determined by how close or how distant the particular register is from the air-conditioning source (equipment).
In commercial new building construction…the close-out activity of the HVAC contractor balancing the air-conditioning in an office space…for example…is critical. Even a few degrees differential in air temperature from one office interior location to another…will bring complaints from the office staff.
In production tract housing and condominiums…balancing the air-conditioning as a final construction activity is for some reason not emphasized. Part of the reason for this is that with economy priced new houses and condominiums…having a relative small square footage serviced by a single interior furnace and a single exterior condenser…the only remedies for adjustment after all of the ducting is in and the system is turned on…is to adjust the register baffles to either restrict or to open up air flow in an effort to balance temperatures throughout the house’s interior.
For high-end, luxury, large square-foot houses having multiple furnaces and condensers…balancing the air-conditioning gets more attention not only because of the high price of the house but also because multiple locations within the structure for furnaces and outside the structure for condensers…allows for the initial design of the system and adjustments made after installation that creates the opportunity for precise air balancing.
For economy level new tract housing and condominiums…air-balancing should be in the scope-of-work section in the HVAC contract. During the homebuyer walkthrough, the builder can also explain to the homebuyer the concept of their adjusting register baffles to fine-tune desired air-flow during the different seasons of the year.