Home Tour
Page 11
Mechanical ventilation Unit Phase 2 Mechanical ventilation Unit
Phase 1 mechanical ventilation unit- Ven Mar (Energy Recovery Ventilator
 Phase 2 mechanical ventilation unit (April Air) connected to the Sears Kenmore dehumidifie
In addition to the efficient HVAC unit, the Pattons followed the other 2 rules of creating a healthy home building envelope- mechanical ventilation (instead of natural ventilation -or opened windows) and dehumidification. Mechanical ventilation systems were used in both building phases. A super efficient, high quality -energy recovery unit (ERV) was used in the phase 1 renovation and addition called Ven-Mar. This unit has an entrelpic wheel within it that supposedly helps to dehumidify the fresh air coming into the house. While not really impressed with the performance of dehumidification in this unit, the Pattons are very impressed with the balanced amount of fresh air flow they get with the Ven-Mar, along with the fact that it is very quiet. This was important because the 900 square foot space is pretty open and the Ven-Mar sits just outside the sleeping loft and above Cindy’s office area. In addition to the Ven-Mar "breathing machine" (as Cindy call’s it) or "the lungs of the home" -a room size energy star rated dehumidifier and room size energy star rated air conditioner are used in the many humid months of the year in WNC. Because the Pattons used the super efficient Poly Icynene insulation in this phase, they are able to cool and dehumidify the entire 900 square feet with single room size units! This is impressive for WNC, considering we are in the extreme moisture belt (or high humidity climate) in the southeast.

The phase 1 building envelope works very efficiently because of the all the components of the "systems approach" the Pattons chose for this phase- working together including the Poly Icynene insulation, the radiant floor heat, high quality mechanical ventilation system, the dehumidifier and air conditioner. The windows in both building phases are the same: double paned, low-e, argon fill glass from Malta (who has now gone out of business –and the Pattons can see why. They are very disappointed in the quality of their windows).

The phase 2 addition mechanical ventilation system consists of an April Air standard air exchanger (not a energy recovery unit like the Ven-Mar- so not as efficient) which is connected (by ducting and a damper) to a room size unit dehumidifier by Sears Kenmore. Cindy and her HVAC installer for phase 2 - designed this system together - keeping the Pattons budget in mind - which was much tighter than the phase 1 budget. After monitoring the performance of this unit for 3 years, they have decided to replace it with a state of the art mechanical ventilation / dehumidification and air filtration unit (all in one) called Ultra Air made by Thermastor products. They are replacing their invention for a couple of reasons:

1. The dehumidifier cannot work hard enough to dehumidify the fresh air from the air exchanger, resulting in the Pattons having to reduce the fresh air flow from the April Air down to about 20% (instead of a 100%) in the summer months because the interior humidity remained too high otherwise. The Pattons augmented the Sears dehumidifier with an additional room size unit dehumidifier as needed in the summer months- which helped the indoor air quality, but increased the energy bills! Ugh!

2. The April Air is not as efficient and quiet as the Ven-Mar (and is also 1/2 the price of the Ven-Mar). For a 3 story house, the Pattons felt a highly efficient air exchanger and dehumidifier/ air filter all in one- would be the most suitable change to make. It will also take up less space than the system they currently have and the energy bills should decrease.

Cindy will update her tour once again after 3 years of monitoring the Ultra Air system.
BACK TO - Tour Page 10
GO TO - Tour Page 12