PSC to ECM motor swap in air handler
In my research of HRV installation I read that if I connect my HRV to the existing duct work I would need to run the air handler can in order to properly distribute the fresh air and that in order to operate the air handler efficiently I would need to use an ECM motor. My current air handler uses a PSC motor so I need to replace the motor, if I install a true ECM motor I would also need to change the control board which is an expensive solution.
After further reading on the net I found several articles discussing using a constant torque motor vice a ECM, the two motors I have seen mentioned are the Genteq Evergreen and the Azure Digi. I have done quite a bit of reading on their websites and the reviews on Amazon (suspect at best) but have not seen any reviews from actual motor test reports.
Can anyone provide me with;
– actual efficiency data for the motors (the data I have found isn’t consistent)
– Reliability data
– reviews from reputable sources
– Pros and cons of the motors
Any suggestions and guidance on these motors or alternatives is greatly appreciated.
Thanks, David
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Replies
One alternative is to get a HRV that has constant flow fans such that it can continue to operate at sufficient CFM with and without the pressures caused by the furnace fan running. But I don't have details (such as which models will do this). Connecting to both supply and return furnace ducts can maintain HRV balance.
If your current controller isn’t for an ECM motor then you’ll need a new controller.
Note that the ECM motor will only save energy if it’s operating with variable speed. A “regular” motor, if properly designed for the load, is pretty efficient too but at one fixed speed. The advantages to variable speed motors is that they can optimize airflow as needed, and the controller only puts in enough energy to drive the motor at the required speed. You can’t just swap motors to gain efficiency, it’s more complicated than that.
Bill
My guess is you would be better off spending the money it would cost to install and operate an ECM motor on a dedicated ductwork system for HRV It will work better and cost less to operate.
Walta