Dow FROTH-PAK Refill Systems - Manual (Page 20)

dow Building Solutions
c) now set the a and B side regulators to their initial
pressure . Turn the handle clockwise to increase the
pressure . a good starting point is 160–170 PSI on the
a Side and 140–150 PSI on the B Side . Higher hose
lengths will require higher pressures . Follow the nitrogen
hoses to the tank and slowly open the nitrogen valves on
the tank to pressurize the tanks . You will hear the nitrogen
flowing as it pressurizes the cylinders . Check for nitrogen
leaks as you are pressurizing the tanks .
d) Slowly open the chemical valves on both the a and B
sides at the tanks to pressurize the hoses . For each side,
there are two valves to open; one valve at the tank and
one ball valve at the filter/hose connection . On the a-side,
open the tank valve first and then open the ball valve .
Repeat for the B side . Check for chemical leaks as you
are pressurizing the hoses .
Note: Should you experience any nitrogen or chemical leaks,
immediate close all chemical and nitrogen valves and correct the
situation before proceeding.
11 . Check the gun to make sure it is working properly .
a) Open the two chemical valves at the gun . You will see
chemical flowing into the gun when they are opened .
b) Fully depress the gun trigger and spray the gun into a
lined waste receptacle to purge the gun and chemical
lines of nitrogen . You should see two good chemical
streams coming from the gun .
c) Spray GREaT STuFF PRO ™ gun cleaner into the face
of the gun to clean away any chemical residue . It is
important to keep the gun face clean to avoid plugging
of the chemical flow and to ensure that the nozzle makes
a leak proof connection .
d) Place a small amount of petroleum jelly on outside face
of gun where the nozzle fits in to ease the process of
attaching the nozzle . It is important that you do not
cover the chemical passage/orifices in the gun with
petroleum jelly .
12 . attach the appropriate calibration nozzle . The calibration
nozzle has 2 tubes protruding from the front of the nozzle .
For calibration purposes, the back cap color of calibration
nozzle should match the color of the spray nozzles that you
intend to use .
13 . The nozzles are a tight fit . Typically you will hear two clicks .
Ensure that the yellow catch is fully latched over the
extension on the nozzle .
14 . label 2 bags; one bag a and one bag B . Place the a side
nozzle in the bag labeled a and the B side nozzle in the bag
labeled B . Fully depress the gun trigger and spray the
chemical into the 2 bags for 5–10 seconds or until the bags
are about 2/3 full .
15 . Weigh the a side first and record the weight (in grams) .
next, weigh the B side and record the weight (in grams or –
be sure to use the same units on the a and B side) .
16 . Calculate the a to B ratio from the data you recorded . Enter
the a Side weight into the calculator and divide it by the B
Side weight . an a to B ratio of 1 .10 to 1 .20 is ideal .
17 . 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 temperature changes to the tanks
and their contents . When in doubt, recalibrate .
Note: If the foam is off ratio (outside of the 1.10 to 1.20 range), adjustment of the
nitrogen regulator will be required.
• If the ratio is below 1.10 for FROTH-PAK ™ Class A Foam Insulation (1.05 for
FROTH-PAK ™ Foam Sealant)
• If the ratio is above 1.20 for FROTH-PAK ™ Class A Foam Insulation (1.15 for
FROTH-PAK ™ Foam Sealant).
• 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. Shut the tank valve.
12