System Purging And Testing; Nozzle Replacement - DuPont FROTH-PAK Manual

11 . Once the tank set has been calibrated, remove the
calibration nozzle, clean the gun face and insert the new
spray nozzle (of the same color) . This calibration is good
until the sets are empty or until you need to replace the
nitrogen tank as long as there are no significant tempera-
ture changes to the tanks and their contents . When in
doubt, recalibrate .
Note: If the foam is off ratio (outside of the stated optimal
range), adjustment of the nitrogen regulator will be required .
• Do not operate the system above 220 PSI on either side,
200 PSI gives an even larger safety factor to avoid opening
the pressure relief valves on the tanks . If you are near this
pressure, then the pressure on the opposite side will need
to be reduced . So if the A Side is near 200 PSI and the ratio
is still too high, bleed down the B Side tank to increase the
differential pressure between the tanks .
• To do this, shut the main nitrogen tank valve and shut the
nitrogen inlet valve on the product tank .
• Slowly loosen the nitrogen hose connection at the regulator .
Do this slowly to let the pressure bleed off .
• Hold the end of the hose in one hand and direct it towards
the ground and away from any people . With the other hand,
slowly open the nitrogen inlet valve on the tank to bleed
down the pressure . Be patient and do this slowly . It may take
a few minutes . You do not need to bleed off all the pressure .
Never bleed below 100psi . Shut the tank valve .
• Go back to the regulator for the hose you disconnected and
turn the handle counterclockwise all the way out .
• Reconnect the nitrogen line and tighten .
• Go back to the regulator for the hose you disconnected and
turn the handle counter clockwise all the way out .
• Reconnect the nitrogen line and tighten .
• Open the tank valve and read the pressure on the tank .
It should be at least 40 – 50 PSI lower than when you started .
• Slowly turn the regulator handle clockwise until the pressure
just starts to increase . You are just bringing the regulator to
the tank pressure . Now set the pressure 20 – 30 PSI lower
than when you last calibrated as a starting point .
• When in doubt, go lower, you can easily increase it if needed .
Repeat as needed until the A to B ration is between 1 . 1 0
and 1 .20 .
Note: The pressure settings are just a starting point . There are
many factors that impact the actual ratio, including material
temperature, hose age and possible partial blockage, and gun
condition . Likewise each set of gauges has a small range of
accuracy . The important thing to remember is that the ratio
calculated during calibration is the FINAL WORD, the tank
pressures are the means to get on ratio . If you need to go
outside the ranges listed above (assuming they are under
220 PSI MAX) that is fine as long as you get the ratio in range .

4.3 System Purging and Testing

1 . DO NOT breathe vapor or spray . Proper PPE and ventilation
are required . See product SDS and Section 2 of this manual
for further information . Follow all precautions for product .
2 . Dispense chemicals in an appropriate container . This is to
verify proper chemical flow .
3 . Clean any chemical from the Insta-Flo
using a rag .
4 . Insert an unused nozzle with the key slot down . Push in
firmly until the nozzle ejector is seated over the back rim
of the nozzle .
5 . Dispense foam into a "test paddy" to verify proper mixing and
ratio . Foam should rise after a few seconds and continue
curing for about 1 minute . Look for off-ratio foam which will
be crispy or soft . If improper foam quality, refer to the
Troubleshooting section, Section 10 of this manual .

4.4 Nozzle Replacement

1 . The life of a nozzle depends on elapsed paused spraying time
and chemical temperature . Replace a previously used nozzle
if the elapsed paused spraying time is exceeded using the
chart on the right as a guide . This chart is for the cone and
Chemical Temp
70°F (21°C)
75°F (24°C)
80°F (27°C)
85°F (29°C)
fan type nozzles . Other specialty nozzles may have different
elapsed paused times .
2 . To replace the used nozzle, push down the nozzle ejector .
The used nozzle should eject .
3 . Insert an unused nozzle with the key slot down . Push in
firmly until the nozzle ejector is seated over the back rim
of the nozzle . The refill system is ready to operate .
Gun face
™
Elapsed Paused
Spraying Time
30 Seconds
30 Seconds
30 Seconds
30 Seconds
13