Lanair MX 75, Installation & Operation Manual

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Call 1-888-370-6531 for Technical Support
Note: The draft gauge should read 0.0 inches of WC when the probe is removed from the
stack. (If not, make sure the gauge is level, and readjust the zero knob). If the heater is not
running, the draft gauge with the probe installed into the stack will not necessarily read zero,
depending on ambient conditions.
The probe may be hot!
Fuel Pressure Gauge: The fuel pressure gauge on the pump outlet should read
approximately 0-5 psi when the pump is operating.
•
If the fuel pressure reading is high, it is an indication that there is a clog in the fuel line
somewhere. Look for crimped tubing, a clogged nozzle or solenoid valve,
obstructions in the nozzle block, or possibly the solenoid valve is not opening
properly. Clean or repair as necessary.
Vacuum Gauge: The vacuum gauge on the inlet of the pump should read between 0 and 5
inches of mercury (Hg). If the vacuum reading is above 5 in. Hg, the filter screen inside the
tank will need to be removed and cleaned. If the reason for high vacuum cannot be
determined, call for Technical Support.
Burn Quality – Visual Check:
When the burner is operating properly, the flame is bright
yellow. If the flame is other than bright yellow, this indicates improper combustion. Contact
Technical Support for help.
The view port is hot. When cool, the viewport may
be removed for cleaning. Do not operate the heater without the viewport in place.
Visual Flame Inspection
View Port
CAUTION - HOT