Heat recovery coils

[SB63]

Are heat recovery coils common in exhaust ducts?

 

[Whoops]

They probably used to be the most common means of ventilation heat recovery. You now see cross-flow plate heat exchangers and thermal wheels doing the same function.

Heat recovery coils are typically 4 or 6 row coils with a lot of fins per inch of tube and are expensive. I think the price of copper has made them less economic than they were 15 or 20 years back.

 

[ChasBean1]

They're also still being designed and installed in large outdoor air volume buildings (particularly lab buildings), where there is a desire for heat recovery but a concern of cross contamination between airstreams.

 

[sethuME]

they are used in huge area of tonnages,where the fresh air load can be reduced with help of HRU

 

[walkes]

They are also used where your outside air and exhaust paths are far apart. The glycol run-around loop helps accommodate some difficult installations.

The content of the exhaust stream may be of concern for the coils, you would have to verify that the coil construction is suited to the environment.