If you are looking for 0% cross contamination energy recovery, a heat pipe might be a good choice for your application. This example features a side-by-side heat pipe and an outside air bypass damper for frost protection. Return air filters and exhaust fans are housed elsewhere outside the AHU, so they are not needed in this case. Electric reheat is used to bump the heat pipe LAT in winter to an even 70F to the space. As of now, the unit is designed for the heating season only, with the option to install a future cooling coil bank down the road for the summer.
