Lanair MXB400 - Manual (Page 37)

1. Separate Air Pre-Heater from Oil Pre-Heater
• Remove o-ring and discard(10).
2. Disassemble Oil Pre-Heater
• Remove o-ring and discard(10).
• Remove six hex cap screws (3) from face plate (2) and discard.
• Remove oil cartridge heater (1).
• Remove four 13/16"OD o-rings and discard(4).
• Remove three plugs (12) from oil block (5)
• Remove hex cap screw (9) from inside oil pre-heater block and clean. NOTE: Do not discard (5).
3. Clean Oil Pre-Heater Block
• Clean oil pre-heater block using a parts washer and brush. NOTE: Make sure all passages are clean.
• Blow dry the oil pre-heater block. inspect ALL passages making sure they are clear and clean.
4. Reassemble Oil Pre-Heater
• Replace four 13/16" OD o-rings (4) with new.
• Replace cartridge heater. NOTE: Do not over-tighten.
• Re-attach face plate (2) using six new hex cap screws (3) provided with tune-up kit (P/N 7240).
• Apply loc-tite to three block plugs (12) and replace.
• Replace hex cap screw (9) inside oil pre-heater block (5).
• Replace o-ring (10) with new.
5. Attach Air Pre-Heater Assembly
• Align the holes of the ignitor assembly and air pre-heater with those of the oil pre-heater (see page 34).
• Attach air pre-heater assembly to the oil pre-heater block (5) using two hex cap screws. Tighten securely.
6. Re-install Pre-Heater Assembly
• Place the air/oil pre-heater assembly into the burner body.
• Align the holes of the pre-heater assembly with those in the burner body.
• Secure the assembly to the body by re-installing the button hex screw (14) and washer (11). NOTE:Do not tighten
this screw at this time.
• Replace the o-rings (7) on the PSI gauge and the oil line fittings (6) with new. NOTE:Do not tighten these fittings at
this time.
• Adjust the pre-heater assembly for proper setting. The end of the turbulator should be recessed approximately 1/4"
into the burner tube (see page 38 for turbulator adjustment).
• Once adjusted tighten button hex screw (14) and fittings (6)securely.
7. Re-connect Electrical
• Re-connect all wires previously disconnected in the electrical junction box (refer to wiring diagram, page 23 and
the burner reference diagram, page 43).
8. Reconnect PSI Gauge, Fuel Line and Air Line
• Reconnect the PSI gauge (8) to the fitting (6) and tighten securely.
• Reconnect the fuel line to the fitting (6) and tighten securely.
• Reconnect the air line by connecting the one end of the air line to the air solenoid and the other end to the
air fitting (see page 34).
9. Test Operation
• Follow start-up procedure, page 26.
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Section 18 - Service / Maintenance