Graco EcoQuip 2 EQp Operation, Repair, And Parts page 26

Operation
Problem
The blast control switch (B) is
not engaged, but blasting
occurs.
While the blast control switch
(B) is engaged, the blast air
flow is fluctuating.
26
Cause
The air supply is inadequate.
The main air regulator is
malfunctioning or is stuck open.
The pneumatic blast control
circuit is malfunctioning.
The supply air pressure is
fluctuating
The main air regulator is
malfunctioning or is stuck open.
The pneumatic blast control
circuit is malfunctioning.
Solution
Make sure the air compressor is capable of
supplying the minimum air flow requirement
for your system (see Technical Specifica-
tions on page 45). Make sure the air inlet
pressure gauge reads 100-150 psi (6.8–10.3
bar, 0.68–1.03 MPa). If the gauge does not
read 100–150 psi, check the air compressor
for proper setup (consult your air compres-
sor manual, see Related Manuals, page 2).
Make sure the air compressor is capable of
supplying the minimum air flow requirement
for your system (see Parts, page 32).
Actuate the blast control switch (B) and
check for proper spool valve actuation in the
4-way valve. If no actuation occurs, check
the blast control switch by disconnecting the
yellow tube at the enclosure male quick dis-
connect and engage the control switch. If
only a little air comes from the fitting, check
the twin-line hose for damage or crimping
and check the pneumatic blast control filter.
If the twin-line and filter are clean, replace
the pneumatic blast control switch. If the
switch is functioning, make sure the yellow
tubing inside the control box is properly con-
nected and clear any obstructions. If all
above items are functional, replace the
4-way solenoid valve.
Make sure the compressor meets minimum
flow requirements and is operating properly.
See Technical Specifications on page 45
for more information.
Disassemble the main air regulator and
check for obstructions. Replace or repair
parts as necessary (see Parts, page 32).
Actuate the blast control switch (B) and
check for proper spool valve actuation in the
4-way valve. If no actuation occurs, check
the blast control switch by disconnecting the
yellow tube at the enclosure male quick dis-
connect and engage the control switch. If
only a little air comes from the fitting, check
the twin-line hose for damage or crimping
and check the pneumatic blast control filter.
If the twin-line and filter are clean, replace
the pneumatic blast control switch. If the
switch is functioning, ensure that the yellow
tubing inside the control box is properly con-
nected and clear of obstructions. If all above
items are functional, replace the 4-way sole-
noid valve.
3A4802D