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Mixing Reset Module 421 - One tN4, Mixing

The Mixing Reset Module 421 is designed to operate all of the mechanical equipment in a hydronic heating system, except for zones, coordinating their operation through network communication. It can be used in applications ranging from a single zone of mixed radiant with an on/off boiler to multiple radiant floor zones with an on/off boiler. This control regulates one mixed heating water temperature through Outdoor Temperature Reset and Indoor Temperature Feedback. It is capable of controlling a single on/off boiler, floating action or variable speed injection mixing, and can expand up to 24 zones in total.

How do I purchase this product?

Contact your Local Representative for details.

Features & Specs

Features (definitions)

Automatic Boiler Differential
Boiler Protection
Exercising
Expandable up to 24 zones
Indoor Temperature Feedback
One touch overrides (with optional User Switch)
Outdoor Temperature Reset
Powered pump outputs
Single on /off boiler control
System setback (with optional timer)
Variable speed, or floating action mixing control
Warm Weather Shut Down
Zone Synchronization

Specifications

Control	Microprocessor control. This is not a safety (limit) control
Packaged weight	1.6 lb (730 g)
Dimensions	3-5/8" H x 5-3/8" W x 9/16" D (92 x 137 x 14 mm)
Approvals	CSA C US, meets Class B: ICES & FCC Part 15
Ambient conditions	Indoor use only, 32 to 122°F (0 to 50°C), RH ≤80% to 88°F (31°C), down to 50% above 104°F (40°C), Altitude <6560 ft. (2000 m), Installation Category II, Pollution Degree
Power supply	Provided by interconnected tekmarNet Zone Manager
Pump relays	115 V (ac) 5 A, 1/6 hp
Variable pump	115 V (ac) 2.5 A, fuse T2.5 A 250 V
Combined load	7.5 A max (System and Variable Speed Pump)
Floating action output	24 V (ac) 8 VA max
Demands	20 to 260 V (ac) / 0.1 VA @ 24 V
Sensors	NTC thermistor, 10 kΩ @ 77°F (25°C ±0.2°C) ß=3892
-Included	Outdoor Sensor 070 and 2 of Universal Sensor 082
Warranty	Limited 3 Year Warranty

Technical

In most cases the current version of literature will work, otherwise use the piece of literature most closely matching the date code of your product.

Current Literature

Product Submittal	Jan 2011 - Present	421_C
Installation & Operation Manual	Aug 2007 - Present	421_D
Job Record	Aug 2009 - Present	421_J
Wiring Brochure	Mar 2009 - Present	421_W