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  Tekmar Boiler Control-One tN4, Four Stage Boiler & DHW/ Setpoint
Tekmar Boiler Control-One tN4, Four Stage Boiler & DHW/ Setpoint
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Tekmar Boiler Control-One tN4, Four Stage Boiler & DHW/ Setpoint

The Boiler Control 274 is designed to stage multiple boilers using Outdoor Temperature Reset. It can be used in applications ranging from a single zone of baseboard, multiple baseboard and fan coil zones, to dedicated domestic hot water heating in commercial buildings. This control regulates a single heating water temperature through Outdoor Temperature Reset and/or setpoint/DHW target control. It is capable of controlling (stage and rotate) up to 4 on/off boilers as well as the system pump.


  • Advanced settings to fine-tune building requirements
  • Automatic Boiler Differential
  • Boiler pump operation
  • Control up to 4 On-Off boilers
  • DHW Priority (optional)
  • DHW pump or valve operation
  • Equal Runtime Rotation
  • Exercising
  • Optional boiler pump(s) operation
  • Outdoor Temperature Reset
  • Powered boiler pump output
  • Primary pump sequencing (optional)
  • Quick setup for easy installation and programming of control
  • Test sequence to ensure proper component operation
  • User comfort adjustment to increase or decrease building space temperature
  • Warm Weather Shut Down


Control Microprocessor control. This is not a safety (limit) control
Packaged weight 3.3 lb. (1550 g)
Dimensions 6-5/8" H x 7-9/16" W x 2-13/16" D (170 x 193 x 72 mm)
Enclosure Blue PVC plastic, NEMA type 1
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 ≤90% Non-condensing
Power supply 115 V (ac) ±10%, 60 Hz, 7 VA, 1150 VA max
Relay capacity 230 V (ac) 5 A, 1/3 hp
Demands 20 to 260 V (ac) 2 VA
Sensors NTC thermistor, 10 kΩ @ 77°F (25°C ±0.2°C) ß=3892
-Included Outdoor Sensor 070, 2 of Universal Sensor 082, and 500Ω Resistor
-Optional tekmar type #:071,078,082
Warranty Limited 3 Year Warranty

Current Literature

Product Submittal

Jan 2011 - Present


Installation & Operation Manual

Nov 2010 - Present


Application Brochure

Nov 2002 - Nov 2003


RF Noise Interference

May 2009 - Present


Energy Savings with Outdoor Reset Brochure


Part Number: 274

2 +$811.56

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