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Troubleshooting
311075ZAB
33
One side doesn’t come up to
pressure in spray mode.
Dirty or damaged Spray valve.
Clean or repair, see
37.
Plugged fluid inlet strainer.
Clear, see
Pump intake valve plugged or stuck
open.
Clean pump intake valve. See step ,
page 38.
Material is too viscous to pump with
unheated unit.
Warm material before adding to
tanks.
Pressure is higher on one side when
setting pressure with function knob.
Pump intake valve partially plugged. Clean pump intake valve. See step ,
page 38.
Air in hose. Fluid is compressible.
Purge air from hose.
Unequal size hoses or unequal hose
construction.
Use matching hoses, or balance
pressures before spraying.
Pressures are not balanced when
running, but pressure is generated
and holds on both strokes.
Unequal viscosities.
Change temperature setting to
balance viscosities.
Change restrictor at mix point to
balance back pressure.
Restriction on one side.
Clean mix module or restrictor at mix
manifold.
Clean gun check valve screens.
Fluid leak in pump packing nut area. Worn throat seals.
Replace. See your pump manual.
Pressure doesn’t hold when stalled
against gun in spray mode.
Leaking Spray valve.
Leaking piston valve or intake valve
in displacement pump.
Repair. See your pump manual.
Leaking gun shutoff.
Repair. See your gun manual.
Pressure is higher on B side during
startup of recirculation, especially in
High Recirc mode.
This is normal. Component B is
typically higher viscosity than
component A until the material is
heated during recirculation.
No action required.
Resin froths and overflows tank after
refilling hot equipment.
Agitation from pouring. Hot material
in heaters and hoses froths when not
under pressure.
Turn heaters off before refilling.
Leave hoses pressurized. See
High Ambient Temperature (above
75°F/24°C)
One gauge shows half as many
pulses as the other when pumps are
cycling.
Loss of pressure on downstoke.
Intake valve is leaking or not closing.
Clean or replace valve; see step ,
page 38.
Loss of pressure on upstoke.
Piston valve is leaking or not closing.
Clean or replace valve or packings;
see
PROBLEM
CAUSE
SOLUTION