Lochinvar has the most advanced and efficient water heating products in the world, and they will find a solution for your project. There isn’t a water heater company that cares more or works harder.

When the KNIGHT boiler was introduced in 2005, it was designed for replacement applications and new construction, and as a result, the KNIGHT boiler was recognized as having phenomenal serviceability and installation flexibility.

Eventually, the Lochinvar boiler line reached up to 800,000 BTU/hr with the introduction of the KNIGHT XL and then the SMART SYSTEM. The SMART SYSTEM control makes operation and setup easier through the color-coded screens, large display, and more.

New and Improved

This KNIGHT boiler is new and improved, with incredible serviceability and reliability. Due to its recent upgrades, it has become the most flexible boiler available. The updates include many standard features that allow PVC, CPVC, polypropylene, or stainless steel to be connected to the boiler. Every boiler is equipped with a 110V convenience outlet, which is used for powering the condensate pump or other equipment.

ECM Pump

The ECM pump is standard on all WHB and KHB boilers. This is because using the Smart System continuously matches the target modulation rates.

Lochinvar KNIGHT Boiler: Features

There are several features of the Lochinvar boiler.

  • Fire-Tube Heat Exchanger
    • This saves on pump operation costs and allows for flexibility of installation while stainless steel keeps away corrosion.
  • Smart System™ Interface
    • The user interface has a diagnostic display with many colors and a code-free interface.
  • 10:1 Modulation Turndown
  • Universal Vent Connector
  • Installation Flexibility
  • Loch-N-Link USB Programming
    • Saves parameters onto a USB drive so you can take it with you.
  • Electrical Outlet
  • There are several SMART SYSTEM features, including LOCH-N-LINK, vacation mode, and ramp delay (which extends runtime and reduces cycling).

KNIGHT Boiler and CON-X-US

With the CON-X-US Remote Connect option, you can control an unlimited number of boilers with the SMART SYSTEM. With the SMART SYSTEM, you can monitor your customer’s boilers to make sure they’re performing up to standard, as well as reset curves and pump delays, adjust domestic hot water, and more.

With the CON-X-US system, you can also set up alerts that will tell you when a boiler needs assistance.


Here are some of the features of the SMART SYSTEM on the Lochinvar KNIGHT boiler:

  • 24 VAC Device Relay
  • Low-Voltage Terminal Strip
  • Domestic Hot Water Recirculation Pump Start/Stop
  • 3 Space Heat Thermostat Contacts
  • Configurable Proving Contacts
  • Alarm on Any Failure Contacts
  • Flow Switch Contacts
  • Runtime Contacts
  • DHW Thermostat Contacts
  • System Sensor Contacts
  • Domestic Hot Water Tank Sensor Contacts
  • Outdoor Air Sensor Contacts
  • Custom Maintenance Reminder with Contractor Contact Information
  • Installer Ability to De-activate Service Reminder
  • Low-Water Flow Safety Control & Indication
  • Password Security
  • Customizable Freeze Protection Parameters
  • Cascade Contacts
  • 0-10 VDC BMS External Control Contact
  • 0-10 VDC Boiler Rate Output Contacts
  • 0-10 VDC Variable Speed System Pump Signal Input
  • 0-10 VDC Signal to Control Variable Speed Boiler Pump
  • Modbus Contacts
    • Time Clock
    • Data Logging
  • Hours Running, Space Heating
  • Hours Running, Domestic Hot Water
  • Ignition Attempts
  • Anti-Cycling
  • Last 10 Lockouts
    • Maintenance Reminder
  • Programmable System Efficiency Optimizers
  • Space Heat Night Setback
  • Domestic Hot Water Night Setback
  • Outdoor Air Reset Curve
  • Ramp Delay
  • Domestic Hot Water Pump
  • Domestic Hot Water Recirculation
    • Domestic Hot Water Prioritization
  • Modulation Factor Control
  • Boost Temperature & Time
    • Four Pump Control
  • System Pump with Parameter for Continuous Operation
  • Boiler Pump with Variable Speed Control
  • DHW tank piped with priority in the boiler loop
  • Separately Adjustable Space Heat/DHW Switching Times
    • Building Management System Integration
  • DHW tank piped as a zone in the system with the pumps controlled by the SMART SYSTEM
  • DHW Modulation Limiting
  • 0-10 VDC Modulation Rate Output
  • Three Sets of Pump Contacts
  • 0-10 VDC Input to Control Modulation or Setpoint
  • 0-10 VDC Input to Enable/Disable Call for Heat
    • Access to BMS Settings through Graphic LCD Display
    • High-Voltage Terminal Strip
  • 120 VAC / 60 Hertz / 1 Phase Power Supply
  • Smart System Control
  • Condensate Trap
  • ECM Variable Speed Boiler Circulating Pump
  • 110V Convenience Outlet
  • High Altitude Models Available
  • Other Features
  • Automatic Reset High Limit
  • Adjustable High Limit w/Manual Reset
  • Boiler Circulating Pump
  • Zero Clearances to Combustible Materials
  • 15-Year Limited Warranty (See Warranty for Details)
  • 5-Year Limited Parts Warranty
  • Firing Codes
  • M9 Standard Construction
  • Vertical & Horizontal Direct Vent
  • PVC, CPVC, Polypropylene or SS Venting up to 100 feet
    • Universal Vent Adapter
  • Built-in Combustion Analyzer Port
    • ENERGY STAR Most Efficient Product
    • 95% DOE AFUE Efficiency (WHB 55-285)
    • Modulating Burner with up to 10:1 Turndown
  • Direct Spark Ignition
  • Low NOx Operation
    • ASME Stainless Steel Heat Exchanger
  • 30 PSI ASME Relief Valve
    • MNPT Top and Bottom Water Connections
  • (WHB 55-285 only)

Optional Equipment

  • Condensate Neutralization Kit
  • BMS Gateway to LON or BACnet IP
  • Multi-Temperature Loop Control
  • Sidewall Vent Termination
  • Wireless Outdoor Sensor
  • LP Conversion Kit
  • Flow Switch
  • Low-Water Cutoff w/Manual Reset & Test
  • Alarm Bell
  • Concentric Vent Kit
  • CON·X·US
  • Remote Connectivity
  • Modbus Communication
  • BACnet MSTP



Specs for the KNIGHT boiler.


Lochinvar Parts Distributors

We distribute boilers and water heaters for Lochinvar. Contact us for more information.