| Dimensions | : | 1.86 in L x 8.85 in W x 14.72 in H |
| Frequency Rating | : | 50/60 Hz |
| Humidity Rating | : | 5 to 90% RH Non-Condensing |
| Number of Zones | : | 4 |
| Temperature Rating | : | 32 to 158 deg F |
| VA Rating | : | 18 VA at 158 deg F, 30 VA at 90 deg F Damper Output per Zone, 18 VA at 158 deg F, 30 VA at 90 deg F Panel and Thermostats |
| Voltage Rating | : | 18 to 30 VAC |
Aprilaire® Control Panel, 18 to 30 VAC, 18 VA at 158 deg F, 30 VA at 90 deg F Damper Output per Zone, 18 VA at 158 deg F, 30 VA at 90 deg F Panel and Thermostats VA Rating, 50/60 Hz, 4 Zones, 5 to 90% RH Non-Condensing Humidity, 32 to 158 deg F, 1.86 in L x 8.85 in W x 14.72 in H
- The 6404 can control up to four-zone and is expandable up to 12 with the use of the model 6401 two-zone expansion panel
- Integrated balance point control
- Equipment protection
- For 2 heat/2 cool conventional and 4 heat/2 cool heat pump applications