H.E.R.O. INDUSTRIES LTD.
1100MD OWNERS MANUAL - “B” VERSION
13
TROUBLESHOOTING
is being pulled backward by the hydrapulse membrane spring, (ref# 48). The backward hydrapulse
membrane movement causes a vacuum in the paint pump. This vacuum causes the intake valve to open,
allowing a new supply of paint to enter. The corresponding paint outgo valve is drawn closed by the vacuum
created by the hydrapulse membrane.
These operations are repeated at a rate of 750 times a minute. These continuously repeated actions draw
paint into the pump, pressurize it, and then deliver it to the gun. The failure, of any one valve, to operate
correctly will effect the overall equipment performance.
Each of the four valves mentioned earlier, have an important function and will effect the overall
performance of the unit if not performing correctly.
HYDRAULIC INTAKE VALVE (REF# 59, PART # 4-30)
The hydraulic intake valve, is a small vacuum valve which controls the hydraulic oil entering the
hydraulic pump/cylinder area. Once the oil has past through the valve it is prevented from returning. The
valve is commonly called a “one way check valve”. Valve failure will result in the hydraulic pump being
unable to build pressure, and the hydrapulse membrane will stop moving. Spray pressure will cease.
HYDRAULIC OUTGO VALVE (REF# 70, PART# 4-27C)
The hydraulic outgo valve, better known as the "pressure control valve", is used to control the units
operating pressure. The valve is fully adjustable from 0 psi. to 3000 psi. By turning the pressure control valve
knob (ref# 71) clockwise the pressure is increased. The hydraulic pump continues to build at all times and
must have a means of releasing this pressure. Pressure applied to the P.C. ball, (ref# 84) will keep it lodged
in the P.C. seat (ref# 83) until the internal hydraulic oil pressure is sufficient to cause it to open. The point at
which the oil is released is equal to the level set by the control knob. As components within the pressure
control valve wear, the valve looses its ability to maintain or reach the required pressures (see "low static
pressure").
PAINT INTAKE VALVE ASSEMBLY (REF# 16-28)
The paint intake valve is made up of nine items, endcap (ref# 16), washer (ref# 17), seat (ref# 18), (ref#
19 not used), intake ball (ref# 20), spring (ref# 21), o-ring (ref# 22), ball guide (ref# 23), ball stop (ref# 24),
O-ring (ref# 25), material head (ref# 27) and cushion (ref# 28). The intake valve controls the incoming flow
of spray materials and is responsible for keeping them from returning to the source. The ball must be able to
create a complete seal on the seat, otherwise pressure will be lost. A worn intake valve will permit correct
static pressure, but supply lower spray pressure. A worn intake ball will become smaller in diameter and
loose its ability to seal at the seat. A worn seat will develop a large step in the area where contact with the
ball is made. This can cause the intake ball to distort in shape making the ball egg shaped. If the valve
assembly becomes warm to the touch, this may be a sign of a loose or worn seat caused by wear or improper
compression caused by a worn intake washer (ref# 17). The intake washer (ref#17), acts as a compression
washer insuring the seat (ref# 18) remains pressed into the endcap (ref# 16). The seat must remain firmly
pressed into the endcap at all times through the correct assembly of parts listed and the correct bolt torque.
Replace the intake washer (ref# 17) each time the endcap is removed. See page 21 for details.
PAINT OUTGO VALVE (REF# 32, PART# 4-11A)
The paint outgo valve monitors and controls the flow of spray materials as it leaves the sprayer. It also
works together with the paint intake valve, to build paint pressure as specified by the setting made by the
hydraulic outgo valve (pressure control valve). A worn outgo valve will result in pulsation in the spray
material and cause the paint hose to jump and vibrate vigorously.
