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The Knight XL - How it works...
1. Stainless steel heat exchanger
Allows system water to flow through specially designed
coils for maximum heat transfer, while providing protection
against flue gas corrosion. The coils are encased in a jacket that
contains the combustion process.
2. Combustion chamber access cover
Allows access to the combustion side of the heat exchanger
coils.
3. Blower
The blower pulls in air and gas through the venturi.
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 the
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 display
Digital controls with SMART TOUCH screen technology, full
color display, and an 7
"
user interface screen.
11. Flue pipe adapter
Allows for the connection of the PVC vent pipe 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)
A 2" (Models 400 - 800) or 2.5" (Model 1000) water connection
that supplies hot water to the system.
14. Water inlet (system return)
A 2" (Models 400 - 800) or 2.5" (Model 1000) copper water
connection that returns water from the system to the heat
exchanger.
15. Gas connection pipe
Threaded pipe connection of 1" or 1 1/4
"
(depending on the
model). This pipe should be connected to the incoming gas
supply for the purpose of delivering gas to the boiler.
16. SMART TOUCH Control Module
The SMART TOUCH Control responds to internal and
external signals and controls the blower, gas valve, and pumps
to meet the heating demand.
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. Boiler drain port
Location from which the heat exchanger can be drained.
20. Low voltage connection board
The connection board is used to connect external low voltage
devices.
21. Low voltage wiring connections (knockouts)
Conduit connection points for the low voltage connection
board.
22. Condensate drain connection
Connects the condensate drain line to a 1/2" PVC connection.
23. Access cover - front
Provides access to the gas train and the heat exchanger.
24. Ignition electrode
Provides direct spark for igniting the burner.
25. Flame inspection window
The quartz glass window provides a view of the burner surface
and flame.
26. Relief valve
Protects the heat exchanger from an over pressure condition.
The relief valve provided with the unit is set at 50 PSI.
27. Flame sensor
Used by the control module to detect the presence of burner
flame.
28. Line voltage wiring connections (knockouts)
Conduit connection points for the high voltage junction box.
29. Top panel
Removable panel to gain access to the internal components.
30. Power switch
Turns 120 VAC ON/OFF to the boiler.
31.
Air box
The air box houses the combustion air filter.
32. Air pressure switch (400 and 800 models only)
The air pressure switch detects blocked flue/inlet conditions.
break the control circuit, shutting the boiler down.
33. Pump relays
The pump relay is used to connect the boiler, system and
DHW pumps.
34.
Transformer
The transformer provides 24V power to the integrated control.
35.
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.
36.
Air Filter (not shown)
The air filter prevents dirt and debris from entering the burner.
37.
Flow Switch
The flow switch is a safety device that ensures flow through
the heat exchanger during operation. This appliance is low
mass and should never be operated without flow. The flow
switch makes contact when flow is detected and allows the unit
to operate. If flow is discontinued during oepration for any
reason, the flow switch will break the control circuit and the
unit will shut down.
Installation & Operation Manual
