PART FOUR: ERV Installations
When we bust ERV myths at BPE, Inc., we aren’t just talking theory. We have demonstrated what today’s super-efficient ERVs can do in the real world. After discussing cross-contamination, efficiency myths, and a case study that demonstrates the excellent IAQ benefits of an ERV in a practical application, we move on to our next ERV myth:
MYTH: “ERVs installations are difficult and complicated.”
Rubbish, we say! For most applications, installing an ERV is as easy as hooking up one Energy Recovery Ventilator and two fans. Air in … air out. In fact, when BPE’s CEO Klas Haglid installed a BPE-MIR-XE-400 unit in his home last week, it took a mere one and a half hours. (Side note: If you recall the case study conducted on his home during our series on radon, Klas found his normal basement level of radon sitting at 4.0 pCi/L. Levels declined by about half to 2.08 pCi/L with his BPE-MIR-XE-200 on the case. The newly installed 400-cfm unit has brought the radon level down to .82 pCi/L. You can bet he and his family are breathing even easier knowing the levels have declined to typical and unavoidable outdoor levels.)
YOU DON’T NEED NO STINKIN’ CRANE! Today’s ERV units can be far easier to lift than their predecessors. BPE units are made of a lightweight, patented monolithic polymer, so you don’t need to be Atlas to set a smaller unit into place. For the bigger, modular, and possibly rooftop jobs, a couple of people can usually get the unit where it needs to go without hiring a crane. Such was the situation when installing rooftop modules on an athletic facility (case study follows).
Example of how BPE ERVs are connected to a Rooftop Air Handler (RTU) to pre-treat the
OA (Outside Air) flow. This helps the unit by starting the process of cooling or heating with air that is nearly the same as the discharge temperature. The alternative is heating up
20-degree air in the winter.
CONFIGURATION SMIGURATION. Stop fretting over which is better: setting an ERV up with its own duct work or connecting it to the HVAC system already there. For most applications, it really doesn’t matter. Remember air in … air out. If you are dealing with an ERV that boasts the high efficiencies of 80 to 98% seen in counter-flow designs, you can afford to lose a little efficiency if the system is not set up optimally. No big deal. This, of course, would not be the case with ERVs that function on an average efficiency of 55%. That said, when it comes to pool or data center installations, you probably want to call in a professional.
BALANCING ACT. What about balancing the airflow? Thanks to an extra-long flow path, BPE ERVs are quite forgiving when it comes to airflow balance for most applications. You might, however, consider adding dampers to ductwork. As long as you ensure that one fan brings fresh air in to pass through the unit’s heat exchanger and another sends the stale air back out of the building, the IAQ and efficiency benefits of an ERV system will outweigh minor imperfections in setup.
Typical fan configuration: Air in … air out.
Regardless of whether your building needs a simple or more complex ventilation setup, it’s good to know help is out there. The engineers at BPE, Inc are always enthusiastic to take your installation questions and challenges. Give us a call.