Series 300 Space Heater Boilers

Series 300 Space Heater Boilers Overview: Triad space heating boilers are the ultimate ready-to-install packaged system featuring a perfectly matched powerful and efficient burner and boiler combination. All necessary boiler controls and secondary plumbing are in place and pre wired, and the vessels easily fit through a 30" doorway, resulting in a very quick start-up.

Firing rates for the Series 300 are available from 210,000 Btu/hr to 375,000 Btu/hr. However, many millions of Btu’s can be delivered by creating an efficient, fully modular system of up to 24 vessels operated by our computerized control panel.

Design: The Series 300 is manufactured to exceed ASME Section IV standards and will typically provide temperatures of between 130-210°F for space heating or process water applications. The vessel capacity is 35 gallons with a heating surface of 34 sq. ft.

These vessels feature 37 vertical firetubes, each of which is 1½" diameter, each fitted with a high-efficiency turbulator for maximum heat transfer. The combustion chamber is fully water-backed, with burners that are UL listed.

This boiler qualifies as a Category I gas appliance with industry standard controls wired to NEC specifications.

Safety: A well-made, heavy boiler is naturally a safer boiler. But TRIAD Boilers also have a firebox design that is completely backed by water, along with extra safety controls on the boiler that results in a very safe and secure package.

Standard Features: The following standard features include nationally known parts and controls that are available at most supply houses, allowing for quick and easy repair and maintenance, which can dramatically reduce down time:

  • UL Listed Gas Trains and Control Systems.
  • Choice of Power Burners.
  • Main and Auxiliary Gas Valves
  • Air Flow Switch
  • Main Manual Leak Test Valve
  • Bell and Gossett Circulating Pump
  • Honeywell Aquastat Relay
  • Automatic Low Water Cutoff
  • Honeywell Second High-Limit With Manual Reset.
  • Burner Control Relay.
  • High Visibility Operating Light.
  • Pressure/Temperature Gauge
  • Pressure Relief Valve
  • 1½" Diameter Firetubes of SA178-A Steel
  • Turbulators for Maximum Heat Transfer
  • Two Inches of Insulation With a Painted Steel Jacket.


Boiler Efficiencies:
Model Input
(BTU/Hr)		 Gross
OutPut		Combustion
Efficiency		 GPM @
Riseº F
210-HEP 210,000 182.28087.0% 18.1 @ 20º F
300-HEP 300,000 258,00086.0% 25.8 @ 20º F
375-HEP 375,000 321,75086.0% 25.8 @ 25º F


Options: TRIAD offers several options to customize your boiler. A job is not complete until the boiler has been properly equipped for the application.

  • Choice of burner manufacturers fired by natural gas, oil, propane, or dual fuel.
  • Fan-Damper relays
  • Barometric Dampers and
  • Galvanized Tees
  • Clean-out openings and plugs
  • Microprocessor Control Panel for true lead-lag modulation
  • Factory built and customized primary mains and headers
  • Immersion Aquastats
  • Various Relief Valve sizes for different applications
  • Lifting Lugs
  • Rail Legs


Boiler Dimensions:
Feature Dimension
  Vessel Width 22"
  Vessel Height 57.5"
  Boiler Weight 800 lbs
  Boiler Depth w/ Burner 36"
  Gas Inlet Height 11"
  Return Water Inlet Height 7"
  Top of Vessel to Bottom Main 8"
  Height to Pump Flange 31"
  Height to Space Heater Return 18.5"
  Height Required at Installation 82"
  Clearance to Rear of Boiler 18"
  Clearance to Front of Boiler 48"
  Clearance to Side of Boiler 18"
  Clearance Between Boilers 3"