Honeywell TH9421C1004 Vision Pro IAQ Thermostat

Honeywell TH9421C1004 Vision Pro IAQ Thermostat

The VisionPRO IAQ touchscreen universal programmable 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.

Customer Reviews: Superb "thermostat" -- actually, it's a whole system controller   January 29, 2010 Filtersmith (Longmont, CO) 1 out of 1 found this review helpful What a splendid device! As an electrical engineer, I wholeheartedly endorse this product. In my house it now controls the humidifier, the whole-house ventilator -- and, more prosaically, the furnace and the air conditioner. That's all from one simple-looking package mounted in the hall, with adjustable backlighting even. I have it set so that it functions as a nightlight, but that's just a byproduct of my not wanting to squint or turn on the hall light to see what the LCD screen says. The menus are simple and natural, and the degree of system control is most gratifying. The homeowner (or his wife) can specify whether the ventilator is permitted to run during sleep time, for just one example. The installation instructions are written so clearly that even a PhD engineer can do it! Nicely, they are separated into Installer and Homeowner levels, so that the homeowner (or his wife, in this case) can't accidentally screw up the installation's intimate details that don't need day-to-day attention. That's house things like square footage, number of bedrooms, etc. It's also technical items like number and types of heating and cooling units (e.g. fossil fuel, electric, heat pump), ventilator's capacity, whether an outside temperature module is included, at what intervals you want to be alerted that it's time to change the filter or humidifier pad, and a welter of other twiddle-knobs to keep a tech-type happy. I bought this through Plumbing Planet with the decision based in part on their satisfaction scores with Amazon customers. I give them very high marks in that regard -- the package arrived on the stated schedule, and it was most professionally packaged. I liked that they included instructions for the thermostat's return, should I have wished to, and in marked difference to other suppliers, they do not require a RMA, or "return materials authorization". That speaks of confidence in their own products. I like to shop locally rather than with distant suppliers, and I'll pay a premium to do so. It adds to my local economy, and significantly it keeps in business the folks whom I can go ask questions of and are more motivated to stand behind their product. For this purchase, however, they could not come within my range of $100 over the price I got from Plumbing Planet. PP sold me this unit for less than my local supplier can buy it direct from Honeywell. We are all puzzled, but it is true. In summary: I am very pleased and would buy it again in a heartbeat. Top of the line residential thermostat   January 19, 2010 JP (Hendersonville, Tunisia) 2 out of 2 found this review helpful Honeywell thermostats are amongst the best available for the home. I got the 9421 thermostat as part of a new heat/air package installation and am very pleased with the choice my installer made. As with many programmable thermostats this thermostat has the ability for individual day settings and two or four periods during the day for wake, leave , return and sleep. Programmable thermostats save a considerable amount of energy vs those with only a single setting. The cost of this thermostat can be recouped several times over during a single cooling season. One nice feature is the ability to have the thermostat automatically switch between heat and cool. Because of this feature heat and cool set points must be at least 3 degrees Fahrenheit apart. If you don't want this feature, you can opt to switch between heat and cool programs manually. I have found that compared to other brands of thermostat the Honeywell is *so* much easier to program. One feature that is missing however is a 'cheat sheet' attached to the thermostat itself as one finds on some other thermostats. This means you better keep the manual safe for programming advanced features. Honeywell thermostats automatically change time as a result of daylight savings time. The need to re-program as often is therefore eliminated. The control panel can be locked out from tampering. Especially nice is that lockout can be set to two different levels. Total lockout, or partial lockout where only current program cycle temperatures can be overridden. Temperatures revert back to program settings when new daytime period occurs. There are many 'advanced features' available through a special 'hidden' menu option. One such feature I like is the ability to set the thermostat to display time as a 24-hour clock. The 8000 and 9000 model thermostats share the same basic features and menu controls. Where the 9000 thermostat differs from 8000 models is the addition of extra features such as Rechargeable lithium backup battery vs 3 AAA alkaline batteries in 8000. Ventilation Control - Home ventilation from 20 minutes up to 180 minutes. Back-light control - Ability to optionally keep back-light on at low light level at all times. 8000 series dim out with no option to leave on. Ability to switch adaptive intelligent recovery off. 8000 series this feature is always active. (Potential energy savings). Additional furnace filter reminder settings. There are extra run time set points plus the addition of calendar days. Restore energy star schedule advanced function. Outdoor temperature display.

7 day  energy saving  programmable thermostat  thermostat  touchscreen