Three-Stage HRV Evaluation

Project Page

In Alaska and Canada, the main defrost strategies for heat recovery ventilators (HRVs) involve recirculating return air across the heat exchanger core and back into the supply air for the house. In cold climates, this type of frost protection system can undermine ventilation standards. To overcome this issue, continuous ventilation systems such as the Zehnder HRV provide frost protection by preheating air before it enters the HRV core, resulting in increased supply air temperatures and preventing the heat exchanger core from freezing. This paper discusses the effectiveness of various frost protection strategies, the energy use of the system, and the effect of continuous ventilation on indoor air quality in a cold climate home.

The full technical report is available here

Related Topics & Keywords: 

Projects

BrHEAThe Evaluation In an effort to address these issues CCHRC developed the BrHEAThe system in 2011. BrHEAThe is a combined heating and ventilation system which uses one distribution system to provide fresh air and space heating to high-performance homes in cold climates.
Energy Recovery Ventilators (ERVs) in Cold Climates Energy Recovery Ventilators (ERVs) are whole house ventilation systems that exchange stale indoor air with fresh outside air, recovering both heat and moisture from the indoor air to save energy. They have the potential to improve indoor air quality in a cold dry climate like Interior Alaska.
Kenai Indoor Air Quality Study This project examined the most common causes of indoor air quality problems in Southcentral Alaska by monitoring 100 homes for carbon monoxide, carbon dioxide, temperature, relative humidity, and radon.
Mold Survey A survey of mold problems in Alaska Native housing looked at 73 regional or village housing authorities in Alaska and documented over 1700 apartments or homes with some degree of mold problem.
Southcentral Ventilation Study This study monitored nine houses in Anchorage to assess the effectiveness of their ventilation system and compliance with the Alaska Building Energy Efficiency Standard ventilation requirements.