Operation; Pressure Relief Procedure; Available Pressures; Air High Inlet Port Operation - Graco A Series Instructions - Parts Manual

Operation

Operation

Pressure Relief Procedure

Follow the Pressure Relief Procedure whenever
you see this symbol.
This equipment stays pressurized until pressure is
manually relieved. To help prevent serious injury from
pressurized fluid, such as splashing fluid, follow the
Pressure Relief Procedure when you stop spraying
and before cleaning, checking, or servicing the
equipment.
1. Shut off the fluid supply.
2. Leave on the air to the fluid regulator.
3. Trigger the gun to relieve the fluid pressure.
4. Shut off the air supply to the fluid regulator.
5. Open the fluid drain valve to relieve all fluid
pressure, having a container ready to catch the
drainage.

Available Pressures

This fluid regulator provides accurate, positive fluid
pressure control to a spray gun or other device. The
regulated fluid outlet pressure is proportional to the pilot
air signal supplied to either the high or low air inlet port.
Each port can be controlled independently.
All three models have the high pressure port, which is
fixed at 1:1. Ratios of 1:1, 1:2, and 1:3 are available for
low pressure applications. The ratio spacer (3, F
color coded to indicate ratio:
• Silver (1:1 ratio)
• Green (1:2 ratio)
• Black (1:3 ratio)
8
See the Performance Data on pages 17 and 18 to help
determine which ratio is best for your application.
Performance is affected by:
• Fluid inlet pressure
• Fluid viscosity
• Size (ID) and length of the regulated fluid outlet line
• Size (ID) and length of the fluid inlet supply line.

Air High Inlet Port Operation

Use the air high inlet port for:
• commanding a higher pressure for faster flushing
• higher fluid viscosities
To operate, shut off the air to the low pressure inlet and
turn on the air to the high pressure inlet.

Air Low Inlet Port Operation

Use the air low inlet port for:
• precise control in critical applications
• lower fluid viscosities
To operate, shut off the air to the high pressure inlet and
turn on the air to the low pressure inlet.

Adjust the Fluid Regulator

The fluid regulator controls pressure downstream from
its outlet. Set the inlet fluid pressure at least 10 psi (.07
MPa, 0.7 bar) higher than the regulated outlet fluid
pressure.
Apply a pilot air signal to either the air high or air low
inlet port. The minimum air pressure depends on the
. 2) is
IG
ratio. See the Performance Data on pages 17 and 18.
If using an accessory fluid pressure gauge, trigger the
air spray gun to relieve pressure in the line when
reducing the pressure, to ensure a correct gauge
reading.
3A0427D