Ventilation Options Expanding
High-performance ventilation choices expanded rapidly in 2018 with several new products that are targeted specifically for supplying continuous fresh, filtered air to airtight, efficient Passive House buildings. Many of the ventilation products now available have undergone independent performance testing regimens, ensuring comparable predictions of energy use intensity and quality. Apples-to-apples testing also cuts through manufacturers’ performance claims, which can be challenging to parse.
In North America there are a variety of options for manufacturers considering ventilation equipment testing and certification. The Home Ventilation Institute (HVI) and the Air Conditioning, Heating & Refrigeration Institute (AHRI) have established third-party industry-led performance testing programs. Since 1998 the Passive House Institute (PHI) has run its own independent performance testing and certification program tailored to the requirements of ventilators for high-performance Passive House buildings. And, now the Passive House Institute U.S. (PHIUS) is in the pilot phase of developing a similar program.
Centralized ventilation with rooftop H/ERV
Courtesy of NK Architects
Semi-distributed ventilation—horizontal (floor-by-floor)
Courtesy of NK Architects
Distributed ventilation with through-wall H/ERV
Courtesy of NK Architects
The Passive House multifamily market, which has seen strong growth in both affordable and market-rate housing, is especially benefitting from this spate of ventilation product developments. Three approaches predominate: distributed, semi-distributed, and centralized. Distributed ventilation relies on one or more small-volume ventilators to bring fresh air to each individual apartment. The equipment may be through-wall HRVs, traditional ducted HRVs or ERVs, or ventilators integrating air heating and cooling. The semi-distributed approach assigns an HRV or ERV of sufficient capacity to service a cluster of multiple units that are in sufficient proximity to minimize duct lengths. The centralized approach relies on a single large HRV or ERV with sufficient capacity for all of the units.
These different approaches tend to blur the traditional distinction between small and large capacity HRVs and ERVs, allowing for more choices when specifying ventilation equipment for even large buildings. Regardless of capacity, the equipment’s thermal and electrical efficiency are essential facts for Passive House design and construction professionals.
Certified for Passive Houses
Last winter, Ontario-based Green Giant Design Build began importing the Futura whole-house ERV for cold climates for distribution throughout Canada. Futura is produced by Jablotron, the Czech Republic home security system giant.
Adam Cronk, owner of Green Giant, explains that the Futura can operate continuously without frosting up at temperatures as low as -12°C. And, with a glycol ground loop, pump, and air handler prewarming air entering the ERV, it can operate at even lower temperatures without costly electric preheating. For night flush cooling during hot, humid summer conditions, the Futura can operate in bypass mode. The Futura comes with a complete ventilation system package including proprietary insulated pipe to the building exterior and a flexible polyethylene interior ducting system.
Although Cronk will remain Jablotron’s sole Canadian distributor, he is building a dealer and installer network to handle sales, installation, and commissioning the Futura in much the same way as Zehnder America operates. This service is particularly important, because in Canada’s harsher climates only a trained installer can optimize the Futura’s operation for a given climate and building.
PHI has certified the Futura ERV, expanding the choices for independently tested ventilators with validated performance for Passive House buildings.
Cronk is not sitting still; he hopes to begin importing additional Jablotron ventilation products in 2019. Stay tuned!
Zehnder America offers a number of PHI-certified HRVs and ERVs for single-family homes, small buildings, and semidistributed ventilation systems for larger buildings.
In 2018, Zehnder America introduced its new ComfoValve Luna S125 supply air diffuser, which adjusts airflow and can distribute it from 240 to 360 degrees with airflow parallel to walls and ceilings.
Ventacity Systems of Portland, Oregon now offers rooftop-capable 1,000 and 3,000 CFM HRVs and ERVs for medium and larger Passive House buildings. Ventacity’s ERVs are the first PHI has certified for large buildings.
Sal D’Auria, CEO of Ventacity Systems, notes their ERVs are both UL and CSA-certified as well. By adding ERVs to their existing line of HRVs, they now have high-efficiency ventilators for every North American climate.
Ventacity’s ERVs have permeable polymer counter-flow cores instead of the HRV’s aluminum core. A simple difference; however, the development process was not so simple. It took over a year of design and engineering of both mechanical components and electronic sensors and controls.
Networked sensors and smart controls are other major 2018 innovations. Ventacity collaborates with Fujitsu General to optimize HVAC systems by combining Ventacity’s HRV or ERV and Fujitsu’s Airstage line of variable refrigerant flow (VRF) commercial heat pump air heating and cooling systems. They operate together as a system with an integrated, wireless electronic monitoring, reporting, and control system that is typically found only in buildings larger than 100,000 square feet.
And these integrated units are ready out of the box. Without add-ons or expensive programming. For Jonathan Moscatello of Ventacity, the partnership with Fujitsu is simple. They are “ready to rock.” “Smarter controls for occupancy, schedules, thermal settings, and CO2 will optimally leverage their high HRV and ERV core efficiency.”
Swegon also offers a range of choices for medium and large Passive House buildings. Eleven models of Swegon’s Gold RX HRVs manufactured in North America are PHI-certified and bear North American safety listings. Swegon’s largest PHI-certified HRVs have a ventilation capacity of up to 5,297 CFM. Swegon also offers its REACT line of dampers which include actuators and controls and operate without a building management system (BMS).
More High Performance Choices
Among the large number of North American manufacturers of ventilation systems of all shapes and sizes, there are several manufacturers and distributors that specifically market their systems for Passive House buildings—but do not have either PHI or PHIUS component certification.
475 High Performance Building Supply is expanding the line of Lunos ventilation equipment it imports from Germany and distributes in the U.S. to meet the demands of the growing Passive House market. With this additional Lunos equipment, 475 can offer Lunos-based distributed HRV systems for multifamily projects in various climates zones.
475 calls these systems hybrids, because they combine Lunos e2 and eGo regenerative thermal core ductless ventilators with heat transfer and demand-controlled intake and exhaust ventilators without heat transfer. Together they supply sufficient fresh air and exhaust sufficient stale air even though some of the air bypasses heat recovery. Floris Keverling Buisman, CEO and technical director explains, “This compartmentalized solution avoids issues normally seen with continuously run rooftop fan systems.”
Although the Lunos e2 does not have HVI or PHI certification, 475 reports the German federal agency DIBt testing established an average heat recovery efficiency of 90.6%. Additionally, 475 provides performance data for use in the ventilation sheet of the PHPP energy balance software.
Tempeff North America, now operationally separate from its Swedish parent, expanded its line in 2018 with its new RGN configuration for installation within a confined space where both exhaust and supply ducts must be connected to the same side of its ERV.
Tempeff’s field mechanical engineer Andy Kebernik explains that Tempeff has supplied ventilators for both PHI and PHIUS-certified buildings in Canada. Tempeff met with PHI in Germany in 2017 to discuss plans for testing and certification, which Kebernik hopes will lead to an agreement with PHI this winter on in-house testing protocols.
UltimateAir of Athens, Ohio continues its 20-year run of leading North American ventilation innovation after pioneering electronically controlled DC motors (ECM) within HRVs and ERVs and water-to-air coils for post- and pre-conditioning ventilation air.
2018 has brought plenty of innovation. UltimateAir developed optional integrated, pulse-modulated electric preheat technology within their ERVs. Jason Morosko, VP, Engineering, explains, “For years, installers were forced to purchase and install these pre-heaters as a separate item for continuous winter ventilation. Integrating the pre-heater within the ERV allows for easier installation in the field, less expensive upfront cost, reduces the chance of condensation, and saves much needed space.”
UltimateAir launched its ER80M as a prototype in 2016, but with modification of its 200DX, in 2018, UltimateAir retested and submitted both models for UL certification under new criteria and received full UL certification for both.
Luke Langhals, director of Business Development promises 2019 will offer continued improvements from the engineering department’s wizardry. “We have begun the R&D for integrating an optional dehumidification accessory into our system.” Stay tuned!
Systems Incorporating Heat Pumps
North America is home to two companies—Build Equinox and Minotair—that incorporate heat pumps in their ventilation equipment instead of using other means to transfer heat and moisture between air streams. Heat pump-based ventilators have the potential to reduce both equipment and installation costs, but for some projects, especially those with smaller living units, the space savings alone make this equipment highly prized.
Build Equinox, based in Illinois, celebrated its 10th anniversary by shipping its first CERV2 units, which integrate both the ventilator and heat pump heating and cooling equipment within the same box. CO2 and VOC monitors are built into the CERV2.
Ben Newell, president and mechanical engineer, explains that the CERV1 system ventilator was in one box with the heat pump in another, but the CERV2 integrates them in a single box for easier installation. While the CERV’s operation is unchanged, the new model’s heat pump is more efficient. The CERV1 was UL-listed, and Newell reports the CERV2 is currently in review for UL listing.
Minotair, based in Quebec, expanded the capabilities of its PentaCare ventilator in 2018 so that now it can both ventilate as well as cool, dehumidify, heat, and/or humidify the ventilation air. Minotair co-owner and VP Alex De Gagné, announced that with an optional, compact humidifier atop the fresh air port controlled by its integrated humidity management system, the PentaCare is “even more valuable in the cold climates where winter outdoor air is so dry that it is difficult to maintain optimum indoor air humidity without humidification.”
For multifamily buildings, Minotair developed a decentralized ventilation and conditioning system combining a remote whole-building control system and its PentaCare units. Each PentaCare unit provides complete HVAC for one apartment, but the building manager has the option to remotely monitor and control the PentaCare units in separate apartments.
De Gagné is in discussions with both PHI and PHIUS about PentaCare certification.
All of these innovations—from new ventilators to new systems combining new and existing equipment—are facilitating multifamily Passive House building ventilation, while continuing to meet the ventilation needs of single-family homes. As this market grows, watch this space for further updates on the whole range of ventilation options.
Tad Everhart, marketing manager for Passive House Buildings, is married to Maria Everhart, Ventacity Systems’ market analyst.