AquaSol Manual - Elm Distribution

AquaSol Manual - Elm Distribution
• SAVE INSTALLATION TIME AND AVOID CALL-BACKS •
• READ THIS MANUAL BEFORE MOUNTING COLLECTORS •
SWIMMING POOL SOLAR
HEATING SYSTEMS
INSTALLATION MANUAL
FOR AQUASOL SOLAR
COLLECTORS
FOR MODEL NUMBERS:
AQ32/322; AQ40/402; AQ48/482
MANUAL CONTENTS
This manual provides a detailed step-by-step procedure for the installation of an AquaSol solar pool
heating system. If the directions are followed correctly and only recommended AquaSol hardware
and components are used, the installed system
should provide years of trouble free service, savings,
and enjoyment.
CAUTION: SOLAR COLLECTORS ARE OFTEN
INSTALLED ON THE ROOFS OF BUILDINGS.
UNLESS YOU ARE VERY FAMILIAR WITH
WORKING ON ROOFS AND HAVE THE PROPER
LADDERS AND SAFETY EQUIPMENT FOR SUCH
WORK, YOU SHOULD HIRE SOMEONE WITH THE
NECESSARY EXPERIENCE TO DO THE
INSTALLATION. FAILURE TO OBSERVE SAFE
PRACTICES ON A ROOF OR OTHER ELEVATED
STRUCTURE MAY RESULT IN FALLING,
LEADING TO SERIOUS INJURY TO YOU.
Page 1 of 13
Page 2 of 13
MOUNTING COMPONENTS
This section provides descriptions and part numbers of
the AquaSol Installation Kits required for each solar
pool heating system. The mounting location of each kit
component is shown by the corresponding circled
number in the ‘Mounting Components’ diagram, shown
above.
2. The System Kit (Part #12135-1 for 1 1/2” kit;
#12135-2 for 2” kit) contains additional hold-down
hardware, connection parts and adapters needed to
complete water connections from the collectors to the
system feed and return line. The pipe adapters that
connect the system piping to the collectors are high
temperature CPVC. Use one (1) kit per system.
Qty 1 1/2”
Qty 2”
1
-
10003-2
-
1
12035-1
1
-
1.5" Hurricane Strap
12035-2
-
1
2" Hurricane Strap
10011
4
4
Hold-down strap clamp assembly
30061-1
1
-
End cap
30061-2
-
1
End cap
Part No
1. The Collector Installation Kit (Part #12034-1 for 1
1/2” kit; #12034-2 for 2” kit) contains the parts
needed to fasten a single solar collector to a
supporting surface and to make water connections
from one collector to another. Hold-down strap is not
included and must be ordered separately Use one (1)
kit per collector.
10003-1
Description
Vacuum Relief Valve
Vacuum Relief Valve
30089-1
2
-
Pipe adapter
Description
30089-2
-
2
Pipe adapter
-
Outlet header hold-down bracket assembly
50006
2
2
Hold-down strap bracket
-
1
Outlet header hold-down bracket assembly
60649-1
2
-
System connector hose (7” long)
50006
2
2
Hold-down strap bracket
60649-2
-
2
System connector hose (7” long)
60648-1
2
-
Collector connector hose (3 3/4” long)
60003-1
4
-
Hose clamp, stainless steel
60648-2
-
2
Collector connector hose (3 3/4” long)
60003-2
-
4
Hose clamp, stainless steel
60003-1
4
-
Hose clamp, stainless steel
60003-2
-
4
Hose clamp, stainless steel
Qty 1 1/2”
Qty 2”
10008-1
1
10008-2
Part No
Page 3 of 13
3. The Add-A-Row Kit (Part #12043-1 for 1 1/2” kit;
#12043-2 for 2” kit) is used when more than one row of
collectors is to be installed. Use one (1) kit for each
collector row after the first.
5.
The Row Spacer Kit (Part #12017-1 for 1 1/2” kit;
#12017-2 for 2” kit) is used when a row of collectors
must be interrupted by a space to allow for obstructions
such as a chimney or roof vent. It contains the hardware
needed to space around any width obstructions by
connecting appropriate lengths of PVC pipe to the pipe
adapters at the inlet and outlet headers of the two collectors on either side of the obstructions. Use when
required.
Qty 1 1/2”
Qty 2”
10008-1
1
-
Outlet header hold-down bracket assembly
10008-2
-
1
Outlet header hold-down bracket assembly
10011
4
4
Hold-down strap clamp assembly
30089-1
4
-
Pipe adapter
30089-2
-
4
Pipe adapter
50006
2
2
Hold-down strap bracket
60648-1
2
-
Collector connector hose (3 3/4” long)
60648-2
-
2
Collector connector hose (3 3/4” long)
60003-1
4
-
Hose clamp, stainless steel
60003-2
-
4
Hose clamp, stainless steel
Part No
4. Hold-Down Strap is required to secure collectors to
6.
Description
Aluminum Mounting Bracket & Header Clamp
Assembly
the mounting surface. Use strap 10035-1 (54’) for rows
of up to 6 collectors or strap 10035-2 (107’) for rows of
up to 12 collectors. Available in bulk, 1400 ft. roll. Part
#10040.
The Aluminum Header Clamp Assembly (Part #10117-1 for 1 1/2”;
#10117-2 for 2”) is used as supplemental outlet header mounting
hardware. It replaces or can be used in conjunction with the Outlet
Header Hold-Down Bracket assembly (100081/-2). The bracket is
designed for installations that require more flexibility for the outlet
header mounting hardware location, such as barrel tile roofs or
installations that require additional mounting hardware to be
anchored into rafters or beams.
7. Header Inserts (Part #50055-1 for 1 1/2”; #50055-2
for 2”) are used in special situations
where unusually high stagnation
temperatures are expected, such as in a
desert climate or where abnormally high
system pressures may occur. Use four
(4) inserts per collector.
8. The Optional Supplemental
Hurricane Collector Hold-Down Kit (Part #12035-1
for 1 1/2”, #12035-2 for 2”) when used in addition to the
basic collector installation kit, meets collector mounting
standards in Florida Counties requiring resistance to
120 mile per hour winds. In regions where high winds
are prevalent, special mounting precautions may be
necessary to secure brackets to the mounting surface.
One method, using threaded rods, is shown here
Page 4 of 13
MOUNTING THE SOLAR COLLECTORS
Refer to Figure 1 throughout this section. When mounting the collectors, always make provisions for inlet connections at the
bottom header and outlet connections at the top. The outlet headers must be pitched a vertical distance of at least 8” (20cm)
above the inlet headers to assure proper drainage and uniform flow. Plan the collector location to allow at least one foot on
all sides of the row of collectors for mounting brackets and piping. The outlet pipe for each row of collectors must be
connected diagonally opposite the inlet pipe. Refer to Figure 2.
Page 5 of 13
1) Determine the position of the last outlet header
hold-down bracket for the row of collectors. Mark this
point on the roof. The collector outlet headers will be
located approximately 1” (25mm) below this mark. Refer
to Figure 3.
2) Using this point, snap a chalkline to the opposite end of
the row. Slope this line down the roof toward the inlet
approximately 1” (25mm) for each 6 collectors in the row.
Using a 1/8” (3mm) drill bit (for 1/4” (6mm) diameter
screws) drill a hole for the first outlet header bracket on
the first roof mark. Measure up 1” on center from the first
pilot hole and drill pilot hole for second screw. Repeat this
process all along the chalkline for the total number of collectors to be installed.
3) Inject a generous amount of high quality sealant into
each hole and onto the surrounding roof surface. Bolt all
the outlet header hold down brackets to the roof as shown
in Figure 4.
4) Locate the hold-down strap bracket holes using the
information in Fig. 1, Table A. Measuring from the top
outlet header bracket chalk line, snap another chalk line
parallel to this line using the “A” dimension. The “B”
dimension is the same for all collector sizes, which is 16”
(40cm) up from the outside of the bottom header and can
be measured after the collectors are installed. Wait to
install the hold-down strap brackets until after the collectors are installed so as not to damage the collectors when
you are bringing them to the roof for installation.
5) Bring the first collector to the roof and slip the proper
hoses over both ends of the inlet and outlet headers on
the last return collector. Make sure that the side of the
collector with the serial number label on it is facing down.
The long hoses go on the outlet of the last collector and
the inlet of the first collector. Push UP TO the hose locating shoulder, but NOT OVER it. Locate a hose clamp
3/8” (10mm) from the end of the hose in order to center it
on the header groove. This clamp must face up so as to
be accessible for tightening and will not rub against the
mounting surface. Make sure you securely tighten each
clamp with a nutdriver. If a nutdriver is not available, a
‘hex’ wrench or screwdriver will suffice. THE HOSE
CLAMPS MUST BE LOCATED OVER THE GROOVES
IN THE HEADER.
6) Position the collector on the roof so that the center of
the outlet connection hoses are directly beneath the
secured outlet header brackets and slip the bracket
hold-down clamps over the connection hoses. Lightly
tighten the clamp around the header hose. Refer to Figure
5. Continue to install all the collectors in the array,
coupling them side to side.
7) If the Aluminum Header Clamp Assembly is to be used
for supplemental mounting hardware, install them after
both the outlet header brackets and the collectors have
been installed.
Page 6 of 13
7) Proceed to the lower chalk line previously snapped on
the roof for the hold-down strap brackets. Mark a hole 2”
(5cm) to the side of the first collector and continue marking holes on the chalkline centered exactly between the
absorber surfaces until you reach the last collector. Mark
the last hole the same 2” (5cm) to the side of the last
collector. Drill a pilot hole and apply sealant at each of
these locations. Bolt the hold-down strap brackets on the
roof. Refer to Figure 6. It is OK to step on the collectors as
long as you stay one foot away from the top and bottom
headers. Mark the holes for the bottom hold-down strap
by measuring up 16” (40cm)from the outside of the
bottom header and again centering them between the
absorbers and 2” (5cm) away from the first and last
collector.
each row. This will be located at the opposite end of the
row that is connected to the collector outlet pipe. Refer to
figure 2, 11, and 12.
9) Install an end cap in the inlet header of each row,
opposite the end that is connected to the collector inlet
pipe. Refer to Figures 2, 11, and 12.
10) INSPECT THE INSTALLATION AND CHECK ALL
CLAMPS FOR PROPER POSITION AND TIGHTNESS.
Slip one end of a hold-down strap through the slot in the
hold-down strap bracket at the end of the row, then
through the strap clamp and out through the other slot in
the hold-down bracket. Pull about 3” (7-8cm) of the strap
through
11) FOR HURRICANE AREAS, REFER TO
ENGINEERING BULLETIN 8101 FOR APPLICATION
OF HURRICANE COLLECTOR HOLD-DOWN KIT (Part
#12035-1 for 1 1/2”, #12035-2 for 2”)
Installation Over Roof Vent Pipes
Collector models with intermittent sonically welded plates
can be installed over or around different diameter roof
vent pipes or other obstructions up to 2” (63mm) in
diameter. After snapping the top chalk lines but before
marking and pre-drilling for your outlet header brackets,
locate the seam in the collector nearest to where the vent
pipe is to come through. Separate by pulling up on top
plate, and pushing down on the lower plate. Should the
vent pipe protrude near a sonic tack weld, it will have to
be cut apart. Using a sharp utility knife, cut through the
weld while pulling the two plates apart. Lay the collector
over the vent pipe, keeping the vent pipe at least 12”
(30.5cm) away from a header. It will be easier to
complete an installation by mounting this collector first
and then working away from it.
Page 7 of 13
With a roof vent pipe of 3” (8cm) in diameter, the collectors
can be positioned on either side of the vent. Two system
connector hoses (Part #60649-1/-2) can be employed to
couple the collectors together for vent pipes or other
obstacles up to 7” (17cm) in diameter. Mark your 51”
(1.3m) centers wherever the outlet header brackets ‘fall’
on the upper chalk line. With obstructions of over 7”
(17cm), such as attic fans and skylights, lay out the collectors on either side of the obstruction using a Row
Spacer Kit (Part #12017-1 for 1 1/2”; #12017-2 for 2”).
System Piping
Refer to Figures 10 & 11, throughout this section. The
most common piping configurations use a pressure filter.
The pump draws the water from the skimmer and/or a
main drain, forcing it through the filter and sending it back
to the pool through the return lines.
If a fuel-fired heater is installed, it is located between the
filter and the return line to the pool. The pipes to and from
the solar collectors are connected to the return line to the
pool
before the water enters the fuel-fired heater, if one is
used. Whenever there is more than 40 gpm (151.6l )
required flow rate to the collectors or more than 100’
(12m) of piping used in a system, install 2” (63mm) piping
to and from the collectors.
Piping to and from the collectors should be the same type
of plastic piping and fittings approved for use with
swimming pool filters and pumps. It is recommended to
always use Schedule 40 PVC pipe and fittings. Although
PVC pipe is generally white, black is also available but
may be difficult to find locally. If for aesthetics black pipe
is desired it can always be painted black. Use a PVC
cutter or a PVC wide-blade saw (not a hacksaw) for
cutting pipe. It is important to use both a quality
cleaner/primer and solvent in gluing a PVC joint. For more
detailed information on PVC gluing refer to Engineering
Bulletin No. 8701. Finally, use a cloth while either gluing or
painting to keep the job a clean one. Piping should also be
supported at intervals of 5’ (1.5m) for horizontal pipe and
8’ (2.5m) for vertical pipe. Use either galvanized or
plastic pipe clamps.
Page 8 of 13
Manual Systems
Some systems can employ a manual control valve to control the flow of water thru the solar collectors, although
this may reduce the overall heating capacity of the
system. The manual control valve usually consists of a
non-positively sealed 3-way valve as shown in Diagram
10. Water continuously flows through the solar collectors
when the filter pump is on, but can be diverted manually
by the pool owner if the pool becomes too warm or during
extended cloudy weather. During a threat of freezing
conditions it can also be diverted, by first shutting off the
pool pump, allowing the collectors to drain, diverting the
3-way manual valve to the “bypass collector” position and
shutting the isolation valves on the collector feed and
return lines. A lower end cap on the collectors or any of
the connecting hoses can be removed to make sure there
is no standing water in the collectors. The filter pump can
then be restarted to allow for normal pool filtration.
During normal operation of the system when the 3-way
valve is in the ‘bypass collector’ position all the water in
the collectors should drain back through the 3-way valve
(nonpositively sealed) when the filter pump shuts off. An
alternate way to protect against sudden freezes can be
accomplished by running a bypass line (1/8”-1/4”,
3-6mm) between the collector feed and return line above
the isolation valves, if any. It is possible that a small
amount of water may be present in the collectors when a
non-positively sealed 3-way valve is used and the filter
pump is on. If a positively sealed 3-way valve is used, a
bypass line as mentioned above is mandatory to allow for
collector drainage.
AUTOMATIC CONTROL SYSTEMS
The performance of a solar pool heating system can be
improved with the use of an electronic control and
motorized 3-way valve. The control activates the
motorized valve and either sends water thru the collectors
for heating (or nocturnal cooling) or automatically
bypasses the collectors when the pool is warm enough or
insufficient sunlight is available. Refer to the
manufacturer’s instructions included with the
automatic control you use.
Other Equipment
Some pools employ an automatic pool cleaner. This
should be plumbed before the control valve to assure
positive flow to the cleaner at all times. If the pool uses an
automatic chlorinator, this should be plumbed after the
outlet tee on the return to the pool.
Flow Rates
In order to receive optimum results from AquaSol
collectors, the following recommended flow rates and
number of collectors per row should be followed. When
the system is
running, all the collectors should feel uniformly cool to the
touch, and there should be no residual air left in the pool
return lines. If either of these two conditions persist,
chances are that the flow rates thru the collectors are
inadequate or the system is not properly balanced. A flow
meter can be installed in the collector feed line to check
on the flow rate. If the flow rates are within the limits as
shown in Table B, then the system may not be properly
balanced, especially with systems requiring multiple
banks of collectors. Refer to the following section on
Special System Layouts.
If the flow rate is below the minimum as shown in the table
above, then the pool pump horse power or pipe size
should be increased, or a booster pump installed in some
cases. If the long hoses on the inlet and outlet piping
connections “suck in”, then slip a piece of 1 1/2” (50mm)
pipe into the hose to prevent this. And also, if the flow rate
is excessive (more than 10 GPM/(37.9l ) collector), or if
the system pressure is greater than 30 psi, a bypass line
should be installed between the collector feed and return
lines above the 3-way valve to prevent problems with the
collectors and connection hoses.
If there is residual air in the pool return lines and the
collectors do feel cool to the touch, refer to the section
concerning the vacuum relief valve test on page 10.
Optional Isolation Valves
Isolation valves may be installed in the collector piping so
that the pool may be operated while the collectors are
being serviced or during freezing weather. Install a
manually operated ball valve in the collector inlet line and
a check valve on the collector return line. Make sure that
the arrow on the check valve is pointing away from the
collectors, and that the ball valve and check valve are
located close to the control valve and outlet ‘T’, respectively. For further precautions in warm climates where
pools are operated year round and periodic freezes can
occur, a bypass line (small diameter tubing) can be
located above the ball and check valve so as to prevent
any accidental trapping of water in the collectors by the
pool owner. To make sure no water is left in the
collectors for servicing or during freezes, remember that
the pool pump should be shut off, allowing the collectors
to drain naturally, before the optional isolation valves are
used.
Page 9 of 13
Special System Layouts
Use a divided system when installing more than the recommended maximum number of collectors per row, when
avoiding roof obstructions, or where limited space
dictates. This provides uniform distribution of water
through all the collectors. If water distribution through the
collectors is non-uniform, the heating capacity of the system will be reduced.
WHEN INSTALLING A DIVIDED SYSTEM, THE OUTLET HEADERS FROM EACH OF THE LOWER (OR
CLOSEST) ROWS OF COLLECTORS MUST BE CONNECTED TO THE HIGHEST (OR FURTHEST) POINT IN
THE SYSTEM. Refer to Figure 11.
A divided system requires an Add-A-Row Kit (Part
#12043-1/-2) for each row of collectors. A more complex
divided system is shown in Figure 12. This also illustrates
the application of the Row Spacer Kit to clear a roof
obstruction.
Booster Pump System
In some cases, the pool filter pump may not be able to circulate water at a high enough flow rate to allow for proper
collector operation. If so, it may be necessary to replace
the filter pump with a larger one or add a booster pump. If
the pump size is increased, it may also be necessary to
upgrade the filter with one with greater flow ratings.
Supplemental Gas, Oil-Fired,
or Electric Heaters
It is desirable to pipe the stand-by heater in a bypass loop.
Refer to Figure 10. Fuel-fired heaters often create a large
pressure drop. By placing a heater in a by-pass
loop, pump size, and electrical energy requirements may
be reduced.
SYSTEM START-UP AND TEST
System Start-up and Checkout
for Automatic Systems
To check out the system for proper operation turn on the
filter system. Set the temperature control to its highest
level. Switch the control to the “flow through collector”
mode. The “flow through collector” light should come on.
The 3 way valve will then be sending water thru the collectors, and air will be purged out of the collectors into the
pool return line for several minutes, and should then clear.
The collectors should feel uniformly cool to the touch.
Switch the control to the “bypass collector” mode. The
corresponding light will go on and the 3 way valve will be
sending water directly back to the pool, bypassing the
solar collectors. After about 5-10 minutes, feel the solar
collectors again. They should have begun to warm up.
Now switch back to the automatic mode. If the sun is still
shining on the solar collectors, the “flow thru collector”
light should go on again. Adjust the temperature control
lower.
When you reach the actual temperature of the pool water,
the light will turn off. The flow bypass collector light will
go on again. Move the temperature control to maximum
and leave there. The “flow through collector” light will go
back on. For more detailed information on the system
startup, trouble shooting and valve/control installation,
follow the manufacturers’ instructions included with the
automatic control system.
Page 10 of 13
Manual Control of System
To test collector operation, follow either the flow-rate or
temperature-rise procedure. Divert water through the collectors. Turn on the pump and either observe flow rate or
temperature rise. The flow rate or temperature rise would
be the same as that specified in the “System Start-Up and
Test” section. If it is not, then check for the indicated
probable causes and make necessary corrections.
Flow Rate Test Method
The preferred system test method is flow rate. This is also
the easiest and quickest method. To check flow rate,
install a flow meter in the inlet line to the collectors (follow
installation instructions provided with the flowmeter).
Temperature Rise Test Method
An alternate test method is temperature rise. To prepare
the system for testing, obtain two accurate thermometers.
AquaSol dial thermometers (Part #60054-2) are excellent
for this application. One of these thermometers is installed
in the outlet line from the collectors as shown in Figure 10.
The other is used to check the temperature of the pool
water, to compare it with that of the water leaving the solar
collectors. Before installing the thermometer in the outlet
line, immerse both thermometers in the pool water for
several minutes to compare the temperature readings. If
they are not identical, make a notation of the
difference and add or subtract (as appropriate) this difference to or from the reading taken while you are testing.
This is necessary in order to provide an accurate indication of the temperature rise of the water passing through
the solar collectors.
Turn the pump on and move the flow switch to the “COLL”
position. Observe valve action...it should divert water
through the collectors. After flow through the collectors
has continued for a least fifteen minutes, compare the
pool water temperature with the temperature of the water
flowing through the outlet line. On an average sunny day,
0
0
with the air temperature approximately 70 F (21 C) the
0
0
water leaving the collectors should be 1 to 7 F (1 to 4 C)
higher than that in the pool. If the water rise is greater
than this, insufficient water is flowing through the
collectors. This may be caused by a clogged filter,
undersized piping, to many elbows in the piping or an
inadequate pump. It is important that the temperature
rise through the collectors be kept as low as possible
in order to deliver the maximum amount of heat to the
pool.
Vacuum Relief Valve Test
When the solar system is first turned on, air in the collectors will be expelled into the pool and bubbles will appear.
The appearance of bubbles in the pool should stop after a
few minutes. If, after a few minutes, bubbles continue to
be discharged at the return to the pool,remove the
vacuum
Page 11 of 13
relief valve(s) and replace it with and end cap. Relocate a
vacuum relief valve to a position in the inlet piping which is
at a height of approximately three-fourths of the elevation
of the collectors above the pool. Refer to Figure 1. (A
quicker alternate method is to first try to reverse the end
cap and the vacuum relief valve on the collector array to
see if this stops the bubbles in the return lines. Sometimes
the end cap is about 3/4 of the elevation of the collectors
and this is a lot quicker than cutting in a tee in the supply
pipe.)
MAINTENANCE
Winterizing Procedures
Annual Service Collector Clamps:
In particularly hot climates, such as Arizona and Southern
Florida, the clamps which are used to connect the solar
collectors may become loose. If you notice leaks around
the hose couplings, use a nutdriver to tighten clamps. Do
not tighten to the extent that the pipe collapses or the
clamp gears strip. In areas where unusually high
stagnation temperatures are prevalent or where
abnormally high system pressures occur, use header
insert (Part #50055-1/-2).
COLLECTOR REPAIR
The solar collectors should drain automatically each time
the pump cycles off. There are no special requirements
for winterizing the solar collectors. The pool piping should
be winterized as per your normal practice. In southern
parts of the country pool owners operate their pools
throughout the winter although light freezing conditions
may occur. The accepted procedure for avoiding
freezing of the pool piping and filtration system has been
to continuously circulate the water. When solar heaters
are used on a pool under these conditions, anti-freeze
precautions should be taken. AquaSol solar collectors are
not normally affected by light freezing. However, in order
to protect appurtenant components such as end caps and
pipe fittings and the collectors against unusual or severe
freezing conditions, one of the following two procedures
should be followed when freezing weather is imminent.
This method allows for an easy and permanent on site
repair of a collector by isolating the leaking riser tube.
Referring to the figure below, locate the tube to be isolated. (End tube has been shown for clarity.) Using a sharp
utility knife, very carefully cut away approximately 1” of the
tube at both headers. Drive a #10 - #12 sheet metal
screw, preferably stainless, into the hole in the header.
The screw must be between 1/2” and 3/4” long. DO NOT
OVERTIGHTEN! If the screw strips out, or if the repair
leaks, use a larger screw. This repair method will not
void the collector warranty.
1. Turn circulating system off and allow solar collectors
and piping to drain. Isolate collectors with gate or ball
valve in collector feed line and a check valve in the collector return line. Switch the solar control to the bypass
position. The pool filtering system may then be turned
back on. When freezing conditions have passed, open
isolation valves and switch the solar control to “AUTO”.
2. Switch the solar control to the “COLL” position so that
water circulates through the collector. When freezing
conditions have passed, switch the solar control to
“AUTO”. THIS METHOD IS NOT RECOMMENDED
WHERE TEMPERATURE LEVELS MAY DROP
SEVERELY.
Page 12 of 13
ELM Distribution
11370 Trade Center Drive
Rancho Cordova, CA 95742
www.aquasolsolar.com
(866) 765-2713
Page 13 of 13
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