ENERGY RECOVERY VENTILATORS FAQs
Answers to your most Frequently Asked Questions about Greenheck energy recovery ventilators.
Q:
Q:Can we incorporate supplemental heating and/or cooling components into an energy recovery unit?
A:
A:Greenheck offers several energy recovery units that incorporate heating and cooling components. Models RVE, ERCH and ERT have several heating and cooling configurations available. Please contact your local Greenheck representative for more information.
Q:
Q:Do Greenheck packaged units have standalone unit controls?
A:
A:Yes, Greenheck packaged units are available with a standalone microprocessor. The microprocessor comes preprogrammed from the factory and offers user-friendly navigation. All sequences are designed and tested in house with factory support available.
Q:
Q:Does Greenheck provide vibration isolated roof curbs?
A:
A:Greenheck currently does not provide any type of vibration isolation or seismic rated roof curbs.
Q:
Q:Does the energy recovery wheel act like a filter?
A:
A:No, the energy recovery wheel does not act like a filter. This component produces laminar/smooth airflow that allows small particles to pass through the wheel. Larger particles may impinge on the wheel surface but can blow off as the wheel rotates to the counter-flowing air stream.
Q:
Q:How does the effectiveness of an energy recovery wheel compare to an aluminum heat exchanger or energy core?
A:
A:Aluminum plate heat exchangers transfer sensible energy (heat) only and have a total effectiveness of 30%. Hydroscopic energy cores will transfer sensible and latent energy and have a total effectiveness of 50-60%. Energy recovery wheels manufactured out of a polymer material with a silica gel desiccant will transfer sensible and latent energy and have a total effectiveness of 70-80%.
Q:
Q:Is it difficult to change an ERV wired for 460/60/3 to 208/60/3?
A:
A:Voltage changes for ERVs can be very time consuming and expensive. You must replace several components to change the voltage. This includes fan motors, fan drives, motor starters, contactors, and overloads. In some cases, disconnect sizes may also change. Finally, you must rerun the wiring to handle the higher amp drawings at the lower voltage.
Q:
Q:Is the energy recovery wheel AHRI certified?
A:
A:Yes, the energy recovery wheel is certified per AHRI 1060. Component and packages certified to this standard are shown in the AHRI Certified Product Directory for Air-to-Air Energy Recovery Ventilation Equipment. AHRI certified ratings include information such as energy transfer effectiveness, pressure drop, and cross leakage (EATR & OACF).
Q:
Q:What certifications do energy recovery units carry?
A:
A:Greenheck energy recovery products carry an ETL listing for electrical safety, AHRI certification for energy recovery components, and an AMCA seal for air performance of the fans. These certifications are important to have on the unit to reassure engineers or owners that the performance published by a manufacturer is the performance that they will actually get.
Q:
Q:What is the cross-leakage rate for an energy recovery wheel?
A:
A:Typical EATR (exhaust air transfer ratio) will be anywhere from 3-5%. AHRI certificates list this information and can be found on the AHRI Certified Product Directory or printed within your CAPS® submittal. Per ASHRAE 62.1, class 3 air (ex. restroom) will allow an EATR of up to 5%, which allows for the usage of an energy recovery wheel.
Q:
Q:What is the energy recovery wheel made of?
A:
A:Greenheck energy recovery products use an "enthalpy" wheel composed of a lightweight polymer embedded with a silica gel desiccant. The polymer media transfers sensible energy (heat) while the silica gel desiccant transfers the latent energy (moisture).
Q:
Q:What is the expected life span of an energy recovery wheel?
A:
A:Energy recovery wheels used in Greenheck products have a typical life span of 15-20 years based on the recommended cleaning and maintenance. In that time, performance of these wheels has been excellent with less than a 5% reduction in latent effectiveness. In addition to the longevity and reliability, Greenheck offers a standard five-year warranty on this component.
Q:
Q:What is the highest turndown ratio available on your indirect gas fired packaged RV/RVE units?
A:
A:The highest turndown ratio for an indirect gas fired furnace in an RV/RVE unit is 16:1. This seamless turndown option allows for precise temperature control and a decreased firing rate resulting in less furnace cycling on part load days. The furnaces can be programmed to maintain a discharge or room temperature controlled via the unit microprocessor or a building management system (BMS).
Q:
Q:What is the recommended cleaning procedure for an energy recovery wheel?
A:
A:Greenheck recommends cleaning the energy recovery wheel and/or wheel segments every two to three years depending on the application. Clean applications that exhaust smoke, oil particles, etc., every two to three months. Use an alkaline detergent solution to clean wheels and rinse with low-pressure water. All wheels and segments should be completely dry before being installed back into the unit.
Q:
Q:What type of applications use energy recovery?
A:
A:Energy recovery is effective in many commercial or institutional comfort ventilation applications. These include schools, dormitories, offices, hotels/motels, nail salons, or restaurants. The Southeast, Midwest, and eastern portions of the United States have excellent climates for energy recovery where there are significant cost/energy savings.
Q:
Q:What type of benefit do the low sound condensing fans provide?
A:
A:Low sound condensing fans offered on models RV and RVE offer several benefits. These condensing fans offer a sound power reduction on average of 5-8 dB and a perceived sound level reduction of up to 50%. The assembly features a serrated fan blade design for increased fan efficiency and an optional EC motor for increased system efficiency.
Q:
Q:What type of salt spray rating does the Hi-Pro Poly coating have?
A:
A:Greenheck's Hi-Pro Poly coating has a salt spray rating per ASTM B117 of 5000 hours. Use the Hi-Pro Poly coating in corrosive environments such those seen with coastal applications.