The Honeywell YTH9421C1010 System is the correct component used with the following:
The Honeywell YTH9421C1010 Total Home Comfort System is a multi-stage VisionPro IAQ programmable thermostat that connects with the Equipment Interface Module or EnviraZONE panel to control temperature, humidification, ventilation and dehumidification from a single point. It includes the YTH9421C1010 Outdoor Temperature Sensor. This programmable thermostat is applicable to conventional and heat pump systems. By automatically raising humidity levels throughout all rooms, moisturizing the air to prevent symptoms of dryness will also protect hardwood flooring and woodwork.
Honeywell YTH9421C1010 Total Home Comfort System Specifications:
The Honeywell YTH9421C1010 Total Home Comfort System is horizontally mounted and used in heat/cool or heat pump applications with auxiliary heat. This programmable thermostat removes air pollutants by exchanging stale air, with fresh, filtered air in the house. It includes humidification control with or without frost protection, dehumidification using whole house dehumidifier or air conditioning with high or low speed fan, advanced patented ventilation control and advanced dual fuel heat pump control.