FLUID SYSTEM DIAGNOSTICS - Flow and Pressure
PROBLEM
POSSIBLE CAUSE
SOLUTION
No Flow
No power
Make sure pump is operating. Check drive belts and couplings, make necessary adjustments.
Trigger gun valve
Check trigger gun, repair or replace.
No water source
Ensure water supply is not restricted and hoses are in good repair and not kinked.
Clogged spray nozzle
Check spray nozzle, repair or replace.
Clogged inlet filter
Check inlet filter, repair or replace.
Float Valve stuck (optional)
Float valves can become stuck in the "UP" position. Manually dislodge and inspect for problems.
Faulty unloader valve
Remove and check for proper action, repair or replace.
Low pressure, adequate
flow
Incorrect or no spray nozzle
Nozzle should be properly sized for the system. Low pressure indicates that the nozzle in use is
too large.
Worn spray nozzle
Replace nozzle when it shows signs of internal erosion.
Debris in valves
Clean valves and check o-rings for pits and cracks.
Lance on low pressure
Adjust pressure so the water flows through properly.
Unloader is not adjusted correctly Adjust unloader to proper level.
Pressure gauge inaccurate
Use a new pressure gauge on a quick connect at outlet to check system pressure and replace if
gauge is faulty.
Pump packings bad
If low pressure persists, pump packings may need replaced.
Low pressure, low flow
Volume Improperly adjusted
If unit has volume adjustment, it may need readjustment
Discharge leaks
Look for leaks on the discharge side of system.
Downstream chemical injector
(Dema)
Remove the injector and retest system. If the flow is restored, replace the injector.
Loose drive belts
If belts do not have proper deflection, replace them.
Pump not running at rated speed
Check engine throttle and see that the motor is rated for the same speed as the pump.
Stripped pump drive coupling
Inspect coupling and repair or replace.
Defective easy start valve
(optional)
Check the start or throttle-back valve for proper operation.
Malfunctioning motor or gear
Ensure that the motor or engine is working properly
Unloader stuck in bypass
Piston assembly may be stuck or fouled
Low pressure, low flow -
Bogs
Outlet restriction
Build up can restrict flow. If water is not flowing freely, flush with garden hose to isolate the clog
or restriction.
Clogged nozzle
Distorted spray pattern can indicate a clogged nozzle.
Nozzle too small
Ensure nozzle is proper size for the system.
Hose restriction
Correct any kinks or restrictions. Replace crushed hoses.
Debris in the system
Debris can lodge in the discharge side of the system (valves, fittings, injectors, filters) Flushing
with water may correct it.
