The ZVAC has a number of features that help distinguish it as the leader in the vertical unit industry. Each feature is discussed in detail in the Features and Benefits section. Excellent efficiency and dehumidification Unique sleeve design for easier installation and service.Three-way slide-out chassis service/maintenance flexibility Electronic Temperature Limiting (requires room air temperature sensor accessory - RAVRMS) Freeze Sentinel™ (requires room air temperature sensor accessory - RAVRMS) Constant ON fan (required in nursing homes in some states) Permanently Lubricated Fan Motors Standard Size Air Filter (20 x 20 x 1) Central Desk Control Capability Occupancy Sensor Interface HI and LOW fan speeds controlled by remote thermostat 3-Speed Indoor Fan Motor for selectable HI and LOW speeds Corrosion Protection Treatment Standard Slinger Ring Condensate Removal Indoor Frost Control Automatic Compressor Random Restart Compressor Restart Delay Quick Heat Recovery (On Heat Pump Units) Extended Heat Pump Operation Reverse Cycle Heat Pump Defrost Warranty (including both parts and labor)