10
Final checks before starting the boiler
Read the Knight XL Service Manual to familiarize yourself with SMART SYSTEM control module operation. Read this manual, page 53 for proper steps to start boiler.
Verify the boiler and system are full of water and all system components are correctly set for operation.
Verify the preparation procedures of Section 10, pages 50 and 51 have been completed.
Fill the vent condensate trap with water (removing the retaining screw in order to remove the 2 inch PVC cap with the switch located at the top of the trap). Replace the cap. Press the cap onto the trap until the cap makes contact with the drain. Replace the retaining screw.
Verify electrical connections are correct and securely attached.
Inspect vent piping and air piping for signs of deterioration from corrosion, physical damage or sagging. Verify air piping and vent piping are intact and correctly installed per this manual.
Installation & Operation Manual
Check vent piping and air piping
1.Check for gastight seal at every connection, seam of air piping, and vent piping.
WARNING Venting system must be sealed gastight to prevent flue gas spillage and carbon
monoxide emissions, which will result in severe personal injury or death.
Check gas piping
1.Check around the boiler for gas odor following the procedure on page 41 of this manual (connecting gas supply piping).
WARNING If you discover evidence of any gas leak, shut down the boiler at once. Find the
leak source with a bubble test and repair immediately. Do not start the boiler again until corrected. Failure to comply could result in severe personal injury, death, or substantial property damage.
Propane boilers – verify conversion
1.Verify propane conversion has been completed per the Propane Conversion instructions.
Start the boiler
1.Read and follow the Operating instructions in FIG.
If boiler does not start correctly
1.Check for loose connections, blown fuse or service switch off?
2.Is external limit control (if used) open? Is boiler water temperature above 200°F (93°C)?
3.Is thermostat set below room temperature?
4.Is gas turned on at meter or boiler?
5.Is incoming gas pressure less than 4 inches w.c. (.99 kPa)?
If none of the above corrects the problem, refer to the Troubleshooting Section of the Knight XL Service Manual.
Check system and boiler
Check water piping
WARNING
WARNING
DO NOT adjust or attempt to measure gas valve outlet pressure. The gas valve is
Knight XL boilers are typically shipped ready to fire on natural gas. Check boiler rating plate to determine which fuel the boiler is set for. If set to natural gas, it may be converted to LP by installing an orifice or by making a gas valve adjustment (see pages 13 and 14). In order to operate on LP gas, an orifice MUST BE installed or a gas valve adjustment MUST BE made. Failure to comply could result in severe personal injury, death, or substantial property damage.
1.Check system piping for leaks. If found, shut down the boiler and repair immediately. (See WARNINGS on pages 50 and 51 (startup) regarding failure to repair leaks.)
2.Vent any remaining air from the system using manual vents. Air in the system will interfere with circulation and cause heat distribution problems and noise.
52 
Check flame and combustion
1.Turn the main power off to the boiler by placing the “On/Off” switch in the OFF position.
2.Remove the flue temperature sensor from the flue pipe connection. NOTE: Combustion measurements will be made at this point.
3.Turn the main power on to the boiler by placing the “On/Off” switch in the ON position.
