The Knight Wall Hung Fire Tube Boiler - How it works...
1. Stainless steel heat exchanger
Allows system water to flow around specially designed tubes
for maximum heat transfer, while providing protection against
flue gas corrosion.
2. Combustion chamber access cover
Allows access to the combustion side of the heat
exchanger.
3. Blower
The blower pulls in air and gas through the venturi (item
5). Air and gas mix inside the blower and are pushed into the
burner, where they burn inside the combustion chamber.
4. Gas
valve
The gas valve senses the negative pressure created by the
blower, allowing gas to flow only if the gas valve is
powered and combustion air is flowing.
5. Venturi
The venturi controls air and gas flow into the burner.
6. Flue gas sensor (limit rated)
This sensor monitors the flue gas exit temperature. The control
module will modulate and shut down the boiler if flue gas
temperature gets too hot. This protects the flue pipe from
overheating.
7. Boiler outlet temperature sensor (housed with the
high limit sensor)
This sensor monitors boiler outlet water temperature (system
supply). If selected as the controlling sensor, the control
module adjusts boiler firing rate so the outlet temperature is
correct.
8. Boiler
inlet
temperature
sensor
This sensor monitors return water temperature (system
return). If selected as the controlling sensor, the control
module adjusts the boiler firing rate so the inlet temperature is
correct.
9. Temperature and pressure gauge (field installed, not
shown)
Monitors the outlet temperature of the boiler as well as the
system water pressure.
10. Electronic LCD display
The display features a high resolution liquid crystal screen, three
(3) buttons, and a navigation dial. A serial and USB port
support additional communication with the control.
11. Flue pipe adapter
Allows for the connection of the vent system to the
boiler.
12. Burner (not shown)
Made with metal fiber and stainless steel construction,
the burner uses pre-mixed air and gas and provides a
wide range of firing rates.
13. Water outlet (system supply)
Copper connection that supplies hot water to the system,
either 1" NPT, 1-1/4" NPT, or 1-1/2" sweat, depending on the
model.
14. Water inlet (system return)
Copper connection that returns water from the system
to the heat exchanger, either 1" NPT, 1-1/4" NPT, or 1-1/2"
sweat, depending on the model.
15. Gas connection pipe
Threaded pipe connection. This pipe should be connected
to the incoming gas supply for the purpose of delivering
gas to the boiler.
16. SMART SYSTEM Control Module
The SMART SYSTEM Control responds to internal and
external signals to regulate the blower, gas valve, and pump
functions to meet heating demand. Optional remote connectivity
allows boiler settings to be monitored and modified when connected
to the internet.
17. Air intake adapter
Allows for the connection of the PVC air intake pipe to
the
boiler.
18. High voltage junction box
The junction box contains the connection points for the line
voltage power and all pumps.
19. Low voltage connection board
The connection board is used to connect external low voltage
devices.
20. Low voltage wiring connections
Conduit connection points for the low voltage
connection
board.
21. Condensate trap (field installed)
The condensate trap prevents flue gasses from escaping the
condensate drain line.
22. Access cover - front
Provides access to the gas valve, control panel, and heat exchanger.
23. Ignition electrode
Provides direct spark for igniting the burner.
24. Flame inspection window
The quartz glass window provides a view of the burner
surface and flame.
25. Relief valve (shipped loose - factory installed on Model
400
only)
Protects the heat exchanger from an over pressure condition.
The relief valve provided with the unit is set at 30 psi.
26. Flame sensor
Used by the control module to detect the presence of burner
flame.
27. Line voltage wiring connections
Conduit connection points for the high voltage junction box.
28. Top panel
Removable panel allows access to the gas train and combustion
chamber.
29.
Gas shutoff switch (Models 056 - 286 only)
An electrical switch designed to cut power to the gas valve to
prevent releasing any gas.
30. Power switch
Turns 120 VAC ON/OFF to the boiler.
31. Auto air vent (Models 56 - 286 only, not shown)
Used to allow removal of trapped air from the heat exchanger.
32.
Transformer
The transformer provides 24V power to the integrated control.
33.
High limit sensor (housed with the outlet
temperature
sensor)
Device that monitors the outlet water temperature. If the
temperature exceeds its setting, the integrated control will
break the control circuit, shutting the boiler down.
34.
Stainless steel flue collector
Flue gas and condensate enter the stainless flue collector through
the fire tubes. A 1 1/4" drain connection allows condensate to flow
through the collector into a condensate trap for disposal.
35. Manual air vent
Used to allow removal of trapped air from the heat exchanger.
For Models 56 - 286 a coin vent is provided in the water inlet cap
for installations where top connections are not used.
4
Installation & Operation Manual
