Lanair MXB360 - Manual (Page 35)

1. Remove Pre-Heater Assembly
• Disconnect the air line from the brass fitting on the air pre-heater and then from
the air solenoid and remove.
• Disconnect wiring from the oil pre-heater cartridge, air pre-heater cartridge and
snap disc assembly in the wiring junction box.
• Disconnect fuel line and fitting (6) from the oil block (5).
• Disconnect fuel pressure gauge (8) and fitting from the oil block (5).
• Remove button hex screw (14) and washer (11).
• Lift pre-heater assembly and carefully pull straight back. Remove entire assembly
from the burner.
• Remove ignitor assembly (6).
2. Remove Diaphragm Assembly from Air Pre-Heater
• Carefully place pre-heater assembly in a vice. NOTE: Do not damage pre-heater.
• Unscrew diaphragm assembly (19) from air pre-heater and set aside. Remove o-ring
and discard.
3. Remove Adapter Assembly
• Remove hex cap screws (17) and set adapter assembly aside.
4. Remove Plunger , Spring and Cartridge Heater
• Remove spring (13) from plunger (15) and discard.
• Using a hook or screwdriver, carefully remove Viton insert (14) and discard.
• Remove and discard 1/4" o-ring (10) and 11/16" o-ring (11).
• Loosen and remove cartridge heater and set aside.
5. Remove Nozzle Assembly and Quad Ring
• Remove nozzle assembly (3) using a 9/16" wrench.
• If quad ring (4) does not come out with nozzle, carefully remove it and discard.
6. Clean all parts using a parts washer
• All passages must be thoroughly cleaned with a brush.
7. Replace Nozzle Assembly and Quad Ring
• After cleaning air pre-heater assembly, blow dry.
• Install new quad ring (4). Before inserting quad ring in air pre-heater block, a light coat of oil should be
applied. NOTE: Make sure quad ring is properly seated in block before proceeding (see page 39 for clarification).
• Apply a light coat of oil to the shaft of the new nozzle assembly (3). Carefully insert new nozzle assembly (3)
through the quad ring and into the block. Hand tighten until snug.
• Check alignment of ignitors and adjust if necessary (see page 38).
8. Replace O-rings and Plunger
• Insert a new 1/4" o-ring (10) and a new 11/16" o-ring (11) into the air pre-heater block (5).
• Insert new Viton insert (14) into the end of the plunger (15) and place new spring (13) on the end of the
plunger. Insert plunger into air pre-heater block spring end first.
9. Replace Cartridge Heater
• Apply pipe dope to cartridge heater threads. Insert cartridge heater into air pre-heater block and tighten.
10. Replace Adapter Assembly
• Align the holes of the adapter assembly (16) with those on the air pre-heater block (5). NOTE: Make
sure the small end of the adapter pin is facing toward the air pre-heater block.
• Attach the Adapter assembly (16) to the block using two hex cap screws (17). Tighten screws.
11. Replace Diaphragm
• Replace diaphragm, o-ring and spring (see page 39) Re-attach diaphragm assembly and hand tighten.
NOTE: Do not over tighten.
12. Replace Ignitor Assembly (see page 39)
13. Service Oil Pre-Heater (see pages 36-37 for Annual Maintenance Instructions)
Visit our website at: www.lanair.com 35
Section 18 - Service / Maintenance
Remove wires from the block by
inserting a flat tip screwdriver
into the top slot. Push tip all the
way down and push forward.
Remove wire.