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MANUALS (2)
Product Highlights
Description
Honeywell Vision PRO IAQ Thermostat provides electronic control of 24 Vac heating and cooling systems in addition to humidification, dehumidification and ventilation all with just 3 wires to the thermostat.. Honeywell TH9421C1004 offers you top-of-the-line features like Touchscreen interaction, a real-time clock, and a large, easy-to-read backlit display.
Features:
- Advanced dual-fuel control
- Three wires to the living space allows for easy equipment upgrade without having to run additional thermostat wire
- Thermostat connects with Equipment Interface Module or EnviraZONE panel to control temperature, humidification, dehumidification and ventilation from a single point in the home
- Automatically raises humidity levels throughout all rooms in the home, moisturizing air to prevent symptoms of dryness and to protect hardwood flooring and woodwork
- Removes air pollutants by exchanging the stale air in a house with fresh, filtered air better than having an open window
Specs
| Amperage: | 1 |
|---|---|
| Application: | Multi-Stage (Heat/Cool) Heat Pump |
| Stages: | 4 Heat/2 Cool Heat Pump 3 Heat/2 Cool |
| Programmability: | 7 Day Programmable |
| User Interface: | Touchscreen |
| Mount: | Horizontal |
| Options: | Fan Control Works with Sensor Large Display Auto Changeover |
| Power Method: | Communicating |
| Changeover: | Auto Manual |
| Temperature Range (F): | 40°F - 99°F |
| Max Temp Differential: | 1°F |
| Operating Humidity: | 5 to 90% RH, non-condensing |
| Voltage: | Low voltage |
| Wattage: | 12 to 30 |
| Wiring: | 1 Rc Y C Vnt2 R 3 Y2 Rh L 2 G |
| Color: | Premier White |
| Height: | 4-9/16" |
| Width (Inches): | 6" |
| Depth (Inches): | 1-1/4" |
| Wireless: | No |
| Humidity Control: | Yes |
Questions?
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Product Reviews
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Works as intended
Sensor Replacwmement
Everything as promised...
Product Q&A
5 QuestionsQ: I IINSTALLED THE SENSOR IN UPSTAIRS APARTMENT,AND THE THERMOSTAT IN THE BOILER ROOM.THE HEAT DID NOT COME ON,IT SHOWED THE TEMPERATURE IN THE BOILER ROOM IS 82 DEGREES,AND UPSTAIRS AT 70 DEGREES.HOW DO I FIX THIS SITUATION
Asked by Shane 13 years ago
Add your answer
1. the thermostat is set to cool; set it to heat.2. The temp setting is the same as the room temp; set it higher; ANDREW G ****@***.***
also, you need to be sure that the indoor sensor is connected as such; this thermostat also has capability for outdoor sensor. the main display would show the temp at the remote indoor sensor as the "inside temp" if it was connected and configured properly. ANDREW G ****@***.***
It seems that the IAQ thermostat is at the factory "0" (default setting) of installation setting #340. You need to check this (refer to the manual) and set it to "1" (remote indoor sensor location only). Ed
Q: Part of the display is not showing up: The up and down arrows. My installer tells me to replace the battery. How do I do this? I removed the digital front from the base. I cannot find any battery cover anywhere.
Asked by jbushouse 13 years ago
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I believe that there is no battery. It is powered from the furnace. Make sure the thermostat is set to either "heat" or "cool", and that the cut-off switch for the furnace is in the 'on' position. In addition, if there is a fault in any of the furnace systems, that would cut the power also. For example, if there is a water pump to pump excess water to a drain from the humidifier/dehumidifier and the pump is not working, then the system will shut down and cause the symptom you describe. Other faults will cause the same symptom. ANDREW G LIPKIN
Under "system" the button on the left of the screen, it most likely shows "off". Touch the "system" button and select "on" or "ac" and then press the "done" button on the bottom left of the screen, your temp buttons will reappear. No, there isn't a battery in the thermostat nor is it needed. Ed
Q: The touchscreen went out on my thermostat - I can just replace the thermostat - I don't have to replace the interface module, do I?
Asked by Penny 15 years ago
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Verified Reply- PexSupply StaffNo, you would not need to change the equipment interface module if you replace the thermostat.
Q: Does this thermostat control a humidier ? When humidity is low does it cut the humidifier in and turn the furnace fan on?
Asked by Murray 15 years ago
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Verified Reply- PexSupply StaffThis thermostat is used for applications with conventional and heat pump systems for humidification, dehumidification and ventilation control. Please have a look at this operating manual for further assistance: http://s3.pexsupply.com/manuals/1249544874360/Honeywell_YTH9421C1002_Operating_Manual.pdf .
Q: will this stat wrk with only three wires with a two stage furnace
Asked by 16 years ago
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Verified Reply- PexSupply StaffThe TH9421C1004 will not control anything directly, it needs to go to the module THM5421C1008 and that can be purchased in kit YTH9421C1004