Service manual

— Page 100 —
© January 2013 Aqua-Hot
®
600-D01 Series Hydronic Heating System Service Manual - Rev. A
APPENDIX C: FUEL PRESSURE CHECK AND ADJUSTMENT
Instructions for Adjusting Fuel Pressure
Step 1: Follow the directions for Checking the Fuel Pressure in this section.
WARNING!
A spark will appear across the ignition electrodes for a brief moment after the diesel burner has been activated.
DO NOT attempt to make any fuel pressure adjustments until the spark has disappeared. Failure to do so may
result in serious bodily injury. In some installations it may be necessary to shine a light on the flame sensor to
simulate a flame condition to shot of the ignition coil.
1. Turn the diesel burner switch to the on position. A pressure will register on the fuel
pressure gauge once the fuel solenoid opens (after approx. 10-20 seconds.
Figure B5
2. Once the fuel solenoid has been activated, and the fuel pressure gauge is registering a
pressure, the fuel pressure can be adjusted. To increase the fuel pressure turn the pressure adjustment
screw clockwise, and to reduce the fuel pressure, turn the pressure adjustment screw counter clockwise.
NOTE: If the fuel pressure cannot be adjusted refer to the fuel pump section in section 10 of this
manual for troubleshooting tips.
Step 2: Adjust The Fuel Pressure to 145 PSI
Figure B6