Interface Module HONEYWELL Prestige 2-Wire IAQ THM5421R1021/U | Montreal, Laval, Longueuil, South Shore & North Shore

A well-equipped home often has more than one heating appliance: a heat pump or a furnace, but also a humidifier, a dehumidifier, an air exchanger. Controlling each one separately complicates daily life. The Honeywell Prestige 2-Wire IAQ THM5421R1021/U equipment interface module centralizes these functions: installed near the equipment, it receives commands from the thermostat and runs the heating, cooling and indoor air quality.

The brain installed next to the equipment

The module mounts in the mechanical room and connects by screw terminals to the HVAC equipment. The thermostat, for its part, communicates with the module by wireless RedLINK or a 2-wire connection. With a RedLINK thermostat, no new wire is needed to the wall: it's a very practical solution when replacing an old thermostat connected with too few wires.

Broad equipment compatibility

The THM5421R1021/U handles up to 4 heating stages and 2 cooling stages on a heat pump, or up to 3 heating stages and 2 cooling stages in conventional mode. It adapts to gas, oil, electric, heat pump, forced-air, hot-water, steam and gravity systems. That versatility makes it a good choice for a forced-air home as well as for a hydronic system.

Three outputs for air quality

The module has three sets of universal contacts for indoor air quality, namely humidification, dehumidification and ventilation. In practice, the same thermostat can control the humidifier in winter, the dehumidifier in summer and the air exchanger all year round. The four sensor inputs accept wired sensors or dry contacts, for example for air sensors or other equipment signals.

Compatibility

The module is designed for Prestige 2-Wire IAQ and VisionPRO with RedLINK thermostats. We confirm your thermostat model before installation.

Installation by AirGreen

The module is hardwired at 18 to 30 VAC, 50/60 Hz, from the equipment. Our technicians:

1. take stock of your equipment: heating, cooling, humidifier, dehumidifier, air exchanger;
2. mount the module near the equipment and connect each appliance;
3. connect any useful sensors or dry contacts;
4. pair the thermostat by RedLINK or 2 wires;
5. configure the stages and air-quality functions, then check each output.

The grey housing measures 237 x 123 x 41 mm and mounts neatly on a mechanical room wall.

Comfort and savings

In a Québec winter, air that's too dry makes the house uncomfortable, even at a good temperature. Well-controlled humidification improves how comfortable it feels. In summer, dehumidification takes load off the air conditioner, and well-managed ventilation renews the air without waste. All from a single thermostat, with consistent logic.

Maintenance

The module itself needs no maintenance. The appliances it controls do: filters, humidifier pads, air exchanger core. We can include them in your annual maintenance visit, so the whole system keeps performing from one season to the next.

Technical specifications

• Type: equipment interface module for indoor air quality
• Stages: up to 4 heating / 2 cooling on a heat pump; up to 3 heating / 2 cooling conventional
• Systems: gas, oil, electric, heat pump, forced air, hot water, steam, gravity
• Air quality: 3 sets of universal contacts (humidification, dehumidification, ventilation)
• Inputs: 4 inputs for wired sensors or dry contacts
• Communication: wireless RedLINK + 2-wire
• Power: 18 to 30 VAC, 50/60 Hz, hardwired
• Connection: screw terminals
• Dimensions: 237 x 123 x 41 mm (9 5/16 x 4 13/16 x 1 5/8 in.)
• Colour: grey
• Compatibility: Prestige 2-Wire IAQ and VisionPRO with RedLINK thermostats

Why AirGreen

AirGreen has been installing heating, cooling, humidification and ventilation systems in the Montréal area for more than 15 years. As a family HVAC business holding an RBQ licence, with a showroom in Boucherville, we know how to connect all your equipment so it works together.

For the purchase and installation of the Honeywell Prestige 2-Wire IAQ THM5421R1021/U module, contact AirGreen. We work in Montréal, Laval, Longueuil, the North Shore and the South Shore.