Lanair HI320 - Manual (Page 49)

SECTION 17 TROUBLE SHOOTING GUIDE
17.1 Initial Diagnosis:
When an operating problem occurs, a determination must be made whether or not
the fuel pump is pumping a sufficient amount of oil that contains no air or water.
Take these steps:
1.
Adjust the burner air regulator to -0- PSI.
2. Turn preheater rocker switch off (red light off).
3. Shut off oil supply line valve to the burner.
4. Remove the fuel supply line from the supply tank.
5. Attach a flexible piece of tubing at least 3 feet long to the outlet on the return
side of the oil by-pass regulator.
6. Insert the tubing into the bottom of a large jar.
7. Jump the cad cell circuit and start the fuel pump, refer to Section 17 (17.2).
8. Attempt to fill the jar above the open end of the tubing.
9. If the pump will not pump fuel, attempt to prime the pump (Section 14). If the
pump won’t prime refer to Section 17 Trouble Shooting, Flow Chart #2.
10. If no air or water is present the flow must be determined.
11. Pump fuel for 1 minute into a graduated container, if the flow rate is less the
250 MILS/Minute (8 ½ Ounces), refer to Section 17 Troubleshooting Flow
Chart #2.
12. If the flow rate is more than 250 MILS/minute (8 ½ Ounces), refer to Section
17 Troubleshooting Flow Chart #3.
13. After repairs are made, remove the cad cell jumper wire, and reconnect the
cad cell wires to the oil primary.
17.2 Bypassing the oil primary safety circuit:
Some trouble-shooting test may require the cad cell safety circuit in the oil primary
control to be bypassed, to do this:
1. Remove the 2 yellow wires from the F-F terminals on the oil primary control.
Warning: Do not operate the heater if the safety circuit is not working!
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