Dual Core Energy Recovery Ventilation System for Northern Housing

Conventional single core heat/energy recovery ventilators (HRVs/ERVs) require de-icing for cold climate operation, often recirculating warm exhaust air through the core back to the indoor to defrost the heat exchanger (defrost cycle). During the defrost cycle no fresh air is delivered to the house and frequent defrost cycles will reduce the amount of outdoor air supplied to the house, leaving the house under-ventilated. Frost protection to ensure a continuous ventilation can be achieved by a preheating system that will often undermine efficiency and will increase the energy cost. This paper presents results on the performance of a novel dual core energy recovery ventilation system that employs a cycling heat exchanger to ensure a continuous delivery of outdoor air to the house. The novel technology was evaluated using climatic chambers, twin houses for a side-by-side testing with conventional single core ERV, and then through extended monitoring in a triplex located in the Arctic. The novel technology was found to be frost-tolerant, capable of withstanding very low outdoor temperatures without deterioration of its thermal performance, and able to provide continuous supply of outdoor air without requiring any defrost strategy or frost protection. The Arctic monitoring of provided evidence of the performance and resiliency of the dual coretechnology, withstanding outdoor temperatures as low as -40°C (-40?) without requiring frost protection and demonstrating sensible effectiveness up to 85% during long winters.