Pumptec PRESSURE WASHER - Manual (Page 6)

6 Version 110112
Pumptec Operating Instructions and Parts Manual PRESSURE WASHER
• After prolonged storage, pump should be purged of air to
facilitate priming. Disconnect the discharge port to allow
liquid to pass through pump and measure flow.
USiNg CHEmiCALS
Chemicals can be mixed into the fluid and it is necessary to
understand whether these chemicals will damage the pump or
other system components. Another way to put chemicals into
the fluid is with a downstream injector.
An injector works as a result of the difference of pressure
between the inlet side of injector and discharge side. In most
cases, the pressure on the discharge side cannot exceed 1/2
of the inlet pressure. For example, 1000 PSI into an injector
should allow up to 500-600 PSI spray pressure on discharge
side. There are dual-function nozzles that permit high pressure,
chemical free rinse and low pressure, chemical spray. These
are convenient for the operator and will not harm a properly
designed system.
The advantages of an injector are:
Fewer items touching chemical, the chemical injection rate
can be controlled, and applying chemical at lower pressure
increases chemical use efficiency.
HEAtiNg FLUiD
The pumps may sometimes be used with downstream heaters
and precautions need to be taken to protect the system and
persons from harm. Refer to the skilled staff at the equipment
manufacturer for guidance and proper system care. Please
be aware that heated water expands and additional pressure
release safety devices may be required.
SyStEm DESigN
A pump is the heart of every system and proper selection is
critical to equipment function and durability. If a pumping set
with excess flow is chosen, then energy and fluid is wasted.
If excess pressure results, then equipment effectiveness can
decrease and so can pump life.
tyPiCAL APPLiCAtiONS AND tHEir
PErFOrmANCE CONSiDErAtiONS
PRESSURE ClEAnIng
The optimal combination of PSI and gPM for cleaning is a ratio
of 1 gPM for every 300-400 PSI. This combination maintains
sufficient droplet size for cleaning force and distance. If the
flow is increased without an increase in pressure, the cleaning
impact does not increase with the increased use of fluid. If
pressure increases, and flow does not, then the water droplet
size reduces and has less impact force, requiring closer cleaning
distances and increased risk of surface damage.
lInE lOSS
When choosing a pump for spraying, pressure loss in the hose
must be considered. The pressure is greatest at pump and
decreases over the length of the hose. Typically, these systems
utilize very long hoses, 200-300 ft. is common, and requires
a certain minimum amount of performance to move the flow
through the lengths of hose. For example, a 3 gPM system will
require (lose) 50 PSI per 50 ft. of 3/8” ID hose. A pump with
only 60-70 PSI may not provide the desired performance at the
end of the hose. See reference charts to assist in system design.
MAINteNANce
DISASSEMBlY AnD REASSEMBlY
InSTRUCTIOnS (Refer to Schematic)
1. Remove pump from motor using a 3/16” hex wrench.
Remove bolts at each end of pump. Turn pump over so
manifold is facing upward. Place manifold to side as a reference
for reassembly.
Figure 1
2. Holding each head, pull them apart to remove plunger.
Remove retaining plate from pump head. Remove internal seal
parts with finger. Discard parts, keeping the head and retainer
plate.
Figure 2