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Control Description The Universal Reset Module 423 provides outdoor reset to a hydronic heating system in order to maximize comfort and efficiency. The 423 can operate two on / off boilers or two modulating boilers. The 423 can override the outdoor reset water temperature to provide Domestic Hot Water or Setpoint operations. The 423 can operate four outdoor reset water temperatures, up to three of these water temperatures can be mixing water temperatures. To operate a mixing device, a Mixing Expansion Module must be connected to the 423 for each mixing water temperature.
Control Microprocessor PID control; This is not a safety (limit) control
Packaged Weight 1.9 lb. (1638 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, CSA/UL 61010-1, meets Class B: ICES and FCC Part 15
Ambient Conditions Indoor use only, 32 to 122¼F (0 to 50¼C).
  RH equal to or less than 92% to 104¼F (40¼C), down to 50% above 104¼F (40¼C)
  Altitude <3000 m (9840 ft), Installation Category II, Pollution Category 2
Power Supply Provided by interconnected Zone Manager
DHW Pump Relay 115 V (ac) 5 A 1/4 hp, pilot duty 240 VA
Primary Pump Relay 115 V (ac) 5 A 1/4 hp, pilot duty 240 VA
Combined Load 10 A Maximum (for DHW and Primary Pump)
DHW Valve Output 24 V (ac) 8 VA Maximum
Modulation Output 0-10 V Minimum 2500 Ω
Boiler Relay 115 V (ac) 5 A 1/4 hp, pilot duty 240 VA
Demands 20-260 V (ac) / 0.1 VA @ 24 V
Sensors NTC thermistor, 10 kΩ @ 77¼F (25¼C ¼0.2¼C) +=3892
Included Outdoor Sensor 070 and Universal Sensor 071


Hide Description

Boiler Reset



Width (Inches):




User Interface:


Push Button



Depth (Inches):


Ambient Conditions:

Indoor Only: 32°-122°F 92% RH up to 104F 50% RH if >104F Altitude<3000m

Power Supply:

From Interconnected Zone Manager


115 V (ac) 5 A-1/4 hp- pilot duty 240 VA;10 A Maximum

Max Temp (F):


Min Temp (F):


Temperature Range (F):

-67°F - 266°F


0-10 V Minimum 2500 Ohms

24 V (ac) 8 VA Max


NTC Thermistor 10 k ohm @ 77°F


070 Sensor

071 Sensor

Weight (lbs):

1.75 lbs


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