Method 4: Flow Hood on Return
| Flow Hood |
Rating | Comments |
|---|---|---|
| Overall Value |  |
Easy to use but very expensive as a system flow meter. May need a larger passive hood for higher flow rate in a single returns and powered flow hood for lower flows of multiple returns |
| Recognized by Standard 310 | Yes | Recognized by ANSI/ACCA/RESNET. |
| Residential Accuracy |
 |
Good accuracy if used on return flows with no duct leakage. Per 310: Only allowed on Grade 1 Duct Leakage results. |
| Consistency | |
Generally Inconsistent readings if leaky ductwork. |
| Equipment Cost |
$$$$$ | Very expensive (~$3000+) for a flow hood. |
| Time (Min) | 4 to 8 | Fast and easy to use. |
