Honeywell THM5421R1021 IAQ Equipment Interface Module

Product Information

I suspect most installers and homeowners will be mostly concerned with how to install the equipment properly and less with the engineering details about how the electronics actually work. When you purchase through links on our site, we may earn an affiliate commission, which supports our community.

Use the Resideo Pro App to install T6 Pro Smart Thermostat in homes, which will associate those homes to your company. Honeywell's Equipment Interface Module (EIM) THM5421R1021 IAQ was supposed to help there -- hooked up to the TACO 406 ZVC in the boiler room instead of the thermostat, and talking to the thermostat via Honeywell's proprietary RedLink-protocol. Sorry, but I'm new to this forum and I couldn't figure out how to do a post other than to reply to this thread. Famous can help you with specifications, product options, design, layout, and coordination of your project from A to Z.As long as I know other installers have conected both the batteries and the 24V at the same time without causing any damage, then for me this issue is laid to rest. It's designed for easy installation and can be used with the THM5421R1012 or THM5421R1021U or THM5421R1021HWREDLINKEQUIPMENTINTERFACEMODULE. My new thermostat booted and I was able to pair it with an in-house and an outside sensors with ease.

Styles from transitional to modern and traditional, you can count on Craft33 cabinets to compliment your clients’ lifestyle and budget. They are also powering the totally wireless communication betweem my stat and the furnace via the equipment interface module which is in turn hard wired to the furnace. Personally, I find the engineering oriented information interesting but sometimes it can be frustrating and confusing when the primary focus is simply how you need to connect the equipment together.This Module will control up to 4-stages of heat and 2-stages of cool in a heat pump system and up to 3-stages of heat and 2-stages of cool in a conventional system. The Honeywell Prestige 2-Wire IAQ Equipment Interface Module delivers easy, reliable connection to your home HVAC system.

You can easily relocate a thermostat or upgrade equipment without running new wires when using this module and a wireless FocusPRO® thermostat. My current Honeywell visionPRO IAQ (TH9421C1004) thermostat is not working as the touchscreen is somewhat dead and unresponsive. Instead of saying it could be powered by either batteries or 24V they should say batteries and/or 24V. I kept the red wire where it was, but switched the white wire from the W to C-terminal on the thermostat and to the "common" terminal in the boiler room (inside a TACO 406 ZVC). Highly compatible with the Honeywell Prestige IAQ System, the THM5421R1021 module saves you time and money.

This statement makes me think that both the 24VAC and the batteries can be connected at the same time because of the backup reference, but I'm not sure. You can change your choices at any time by visiting Cookie preferences, as described in the Cookie notice. The Honeywell Prestige 2-Wire IAQ Equipment Interface Module is an essential part of the home HVAC system.