Graco AquaMax 3540GHW, Instructions Manual

Page: 19 / 38

Troubleshooting
Water is leaking under heat ex-
changer coil. Coil drain plug is not installed. Install.
Safety relief device is relieving
caused by an unloader or pressure
switch problem. Detect and correct unloader or pressure
switch problem.
Replace safety relief device. Never run
unit without safety relief device. Doing so
can cause an explosion.
Burner will not ignite. Burner switch is not turned on. Check switch position.
Out of fuel. Refuel.
Trigger gun is closed. Open trigger gun for pressure.
EMF Drive belt loose or broken. Adjust or replace as necessary.
Flexible coupler broken. Replace.
Dirty or clogged fuel filter/water sep. Drain or replace as necessary.
Fuel pump sucking air. Tighten all fuel intake connections. Elimi-
nate leaks in intake line.
Fuel pump inoperative. Check pressure, replace if needed.
Fuel pickup screen is obstructed. Consult Service.
Dirty or clogged fuel nozzle. Replace fuel nozzle.
Ignition module. Consult Service.
Ignition electrodes damaged or
worn. With unit running and trigger gun closed,
look through burner sight glass to ensure
there is sparking across electrodes.
No voltage. Consult Service.
Pressure switch override. Pressure should be over 250 PSI/18 Bar
to allow burner to come on.
Highlimit switch override. Allow unit to cool down before reigniting.
Improper burner air adjustment. Adjust as shown on page 16.
Fuel solenoid valve failure. Replace.
Burner runs erratically. Water in the fuel oil. Drain fuel filter/water separator, drain fuel
tank and replace with clean fuel.
Dirty fuel filter/water separator. Replace element.
Dirty fuel nozzle. Replace.
Improper air adjustment setting. Adjust as shown on page 16.
Fuel pickup screen is obstructed. Consult Service.
Fuel pump malfunctioning. Replace.
Burner runs, but will not heat Poor or improper fuel supply. Check fuel to ensure it is correct. Drain
tank and filter if necessary and refill with
proper fuel.
Low fuel pump pressure. Check fuel pump pressure, replace if
needed.
Dirty fuel nozzle. Replace.
Improper air adjustment setting. Adjust as shown on page 16.
Fuel pickup screen is obstructed. Consult Service.
Scale build up in heat exchanger coil. Consult Service.
Burner discharges white smoke. Low on fuel Refuel. If white smoke persists, consult
Service.
Excessive air supply. Adjust as shown on page 16.
Burner discharges black smoke Insufficient air supply. Adjust as shown on page 16.
Problem Cause Solution