dosatron D8RE3000 Operating instructions

Page 1
1-800-523-8499 • www.dosatronusa.com
Proper protection, such as gloves, eyewear, and aprons, are recommended when disassembling a Dosatron.
D8RE3000 Troubleshooting
Page 1
D8RE3000 Troubleshooting
To troubleshoot your D8RE3000
injector you will need a strap
wrench (Part #: TOOL01), needle
nose pliers and a utility knife.
NOTE: It is best to perform this
maintenance in a clean area or if
your Dosatron unit is in-line, cover
your concentrate tank so you won’t
lose any of the parts.
pages 2 - 6
pages 7 - 8
pages 9 - 11

Page 2
1-800-523-8499 • www.dosatronusa.com
Proper protection, such as gloves, eyewear, and aprons, are recommended when disassembling a Dosatron.
D8RE3000 Troubleshooting - Part 1
Step 3: Slide the ferrule back and cut a half inch off the top of the
hose. Reposition the ferrule to original position.
Step 2: If there is no suction, unscrew and remove the hose nut.
If your Dosatron is clicking but not drawing the concentrate,
it could be as simple as the strainer is plugged with debris.
Step 1: Take a look at the strainer. If it is clogged, just clean it and
re-test your Dosatron unit.
This D8RE3000 - 40 GPM Troubleshooting Part 1 will cover: The injector is clicking, but
not drawing the concentrate.

Page 3
1-800-523-8499 • www.dosatronusa.com
Proper protection, such as gloves, eyewear, and aprons, are recommended when disassembling a Dosatron.
D8RE3000 Troubleshooting - Part 1
Step 6: Press the air bleed button on the bell housing a few times
to release the pressure.
Step 5: After you reinstall the suction hose, turn on the water. You
should start to see the liquid begin moving up the hose.
If the liquid is not moving up the hose after a minute or so, just turn
the water off.
Step 4: Insert the hose back into the barb and hand tighten
the nut.
Note: If the hose (Part #: 4MM) is cracked, or looks really old, just
replace it now.

Page 4
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Proper protection, such as gloves, eyewear, and aprons, are recommended when disassembling a Dosatron.
D8RE3000 Troubleshooting - Part 1
Step 9: Then, pull the injection stem straight out of the injector’s
body and set aside.
Step 8: Unscrew the injection stem nut and remove.
Step 7: To continue, unscrew the suction hose nut once more and
set the hose aside.

Page 5
1-800-523-8499 • www.dosatronusa.com
Proper protection, such as gloves, eyewear, and aprons, are recommended when disassembling a Dosatron.
D8RE3000 Troubleshooting - Part 1
Page 5
Step 11: To remove the beige plunger, pull it down as far as it
will go.
Step 10: Take a close look at the plunger rod and seal. Make sure
the rod is straight and that the seal is free of nicks, scratches, or
wear.
NOTE: If the plunger or seal is damaged or you don’t remember
the last time you changed it, just replace the plunger assembly
(Part #: 8PJ074) now.
Step 12: Position the needle nose pliers near the top of the
plunger and carefully twist it a quarter turn counter clockwise,
as pictured, and disconnect.
To install the new plunger assembly (Part #: 8PJ074), use the
needle nose pliers to align the top of the plunger with the retainer.
Then twist it a quarter turn clockwise to lock.

Page 6
1-800-523-8499 • www.dosatronusa.com
Proper protection, such as gloves, eyewear, and aprons, are recommended when disassembling a Dosatron.
D8RE3000 Troubleshooting - Part 1
Step 15: Now, slide the hose into the barb and hand tighten
the nut. Pull on the hose to make sure it’s connected securely.
NOTE: If the hose comes off easily, you may need to cut another
half inch off, reset the ferrule and reattach the nut.
Test the unit by slowly turning the water on. The unit should
begin drawing the concentrate.
Step 14: Align the notches in the lower part of the blue body with
the teeth on the top of the injection stem assembly. Slide the two
parts together, and hand tighten the injection stem nut.
Step 13: Grab the injection stem assembly and carefully slide it
onto the plunger as pictured.

Page 7
1-800-523-8499 • www.dosatronusa.com
Proper protection, such as gloves, eyewear, and aprons, are recommended when disassembling a Dosatron.
D8RE3000 Troubleshooting - Part 2
Step 3: Grasp the white threaded barb and pull the check valve
assembly straight out. It might come out in two pieces. Set the
unit aside.
Step 2: Unscrew and remove the check valve nut.
If your Dosatron injector is pushing water down into the
concentrate tank, it’s time to investigate the check valve.
Step 1: Remove the hose nut and set it aside.
This D8RE3000 - 40 GPM Troubleshooting Part 2 will cover: The injector is clicking but
is pushing water down into the concentrate tank.

Page 8
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Proper protection, such as gloves, eyewear, and aprons, are recommended when disassembling a Dosatron.
D8RE3000 Troubleshooting - Part 2
Step 6: Now slide the hose into the barb and hand tighten the nut.
Afterwards, pull on the hose to make sure it’s connected securely.
NOTE: If the hose comes off easily, you may need to cut another
half inch off, reset the ferrule and reattach the nut.
This should stop the water from going back into the concentrate tank.
Step 5: To reassemble, place the new check valve assembly into
the top of the barb.
Reinstall the check valve and the check
valve nut. Hand tighten.
Step 4: To inspect the check valve, carefully lift the cone from the
retainer and look at the bottom side of the cone. Then, carefully
lift the retainer from the seal. You are checking to see if there is
anything lodged or stuck.
NOTE: Do not try to remove the spring. If the spring is deformed
or stretched, the complete assembly (Part #: PJDI140) must be
replaced. If you see damage or don’t remember the last time you
changed these parts, replace them now.

Page 9
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Proper protection, such as gloves, eyewear, and aprons, are recommended when disassembling a Dosatron.
D8RE3000 Troubleshooting - Part 3
Step 3: Grasp the white plastic bridge on top of the piston and pull
it straight out.
Step 2: Use the strap wrench (Part #: TOOL01) to loosen the bell
housing. Unscrew, remove and set it aside.
If the Dosatron injector is not clicking or is stalling at low
ow, we need to investigate the piston.
Step 1: Turn the water off and press the air bleed button a few
times to release the pressure.
This D8RE3000 - 40 GPM Troubleshooting Part 3 will cover: The injector is not clicking
or is stalling at low ow.

Page 10
1-800-523-8499 • www.dosatronusa.com
Proper protection, such as gloves, eyewear, and aprons, are recommended when disassembling a Dosatron.
D8RE3000 Troubleshooting - Part 3
Step 4: Holding the piston, press the push rod up and down. It
should click in both directions. If not, please give us a call for
assistance or check out the D8 Piston Shell and Actuator
Assembly Replacement Service Video.
Step 5: Next, visually inspect the upper and lower anges on the
piston shell. If they are worn or have deep scratches, the piston
shell (Part #: 8PC002) needs to be replaced.
If either is loose, the piston shell needs to be replaced.
To test the upper ange, invert the piston
and insert it squarely halfway into the blue
bell housing. It should stay in place.
To test the lower ange,
use the needle nose pliers
to twist the plunger counter
clockwise and remove.
Then, insert the piston
squarely into the body about
halfway - it should stay in place.
For assistance in replacing the piston shell, please contact
Dosatron technical service at 1-800-523-8499 or check out the D8
Piston Shell and Actuator Assembly Replacement Service Video.
Another way to check the anges is by doing a FIT TEST :

Page 11
1-800-523-8499 • www.dosatronusa.com
Proper protection, such as gloves, eyewear, and aprons, are recommended when disassembling a Dosatron.
D8RE3000 Troubleshooting - Part 3
Step 7: Place the piston back into the body and reinstall the blue
bell housing, hand tighten.
We hope this document has been helpful in troubleshooting your
Dosatron D8RE3000- 40 GPM Injector.
For more information, give us a call at 1-800-523-8499 or visit us online at www.dosatronusa.com.
To see our videos, check out our YouTube channel.
Step 6: If you removed the plunger in the last step, reattach now
using the needle nose pliers, by aligning the top of the plunger
with the retainer. Twist the plunger clockwise to lock.