dosatron D 25 F 1 Operating instructions

Page 1
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www.dosatronusa.com
Proper protection, such as gloves, eye wear, and aprons, are recommended when disassembling a Dosatron.
Step 3: Then, remove the hose.
Step 2: If there is still no suction, turn the water on. If the
Medicator is clicking, unscrew and remove the suction hose nut.
NOTE: To service your D25F Medicator you will need a strap
wrench (Part #TOOL01) and a small tip Phillips head screwdriver.
Step 1: If your Medicator is clicking, but not drawing concentrate,
it could be as simple as the strainer is plugged with debris. Take
a look at the strainer. If it is clogged, clean it out and re-test your
Dosatron.
D25F Troubleshooting - Part 1
This D25F Troubleshooting will cover: The Medicator is not drawing the concentrate,
but is clicking.
Scan the QR code
to watch our D25F
- Troubleshooting
video.

Page 2
800-523-8499
www.dosatronusa.com
Proper protection, such as gloves, eye wear, and aprons, are recommended when disassembling a Dosatron.
Step 6: If you don’t see liquid moving up the tube or you don’t feel
suction on your nger, turn the water off. Press the air bleed button
on the lid a couple times to release the pressure.
Step 5: If you feel suction, just cut a half inch off the top of the
hose and reattach. You should see the liquid begin moving up the
suction tube.
Step 4: Check to see if you feel suction on your nger.
D25F Troubleshooting - Part 1

Page 3
800-523-8499
www.dosatronusa.com
Proper protection, such as gloves, eye wear, and aprons, are recommended when disassembling a Dosatron.
Step 9: Grasp the white valve support and pull the piston straight
out of the body.
Step 8: Unscrew to remove.
Step 7: Using a strap wrench (Part #: TOOL01), loosen the lid.
D25F Troubleshooting - Part 1

Page 4
800-523-8499
www.dosatronusa.com
Proper protection, such as gloves, eye wear, and aprons, are recommended when disassembling a Dosatron.
Step 12: Install the new seal (Part #: J009) into the groove.
Step 11: To replace the seal, pinch and roll it off of the plunger.
Step 10: Take a close look at the plunger seal for nicks, scratches,
or wear. If you see damage or don’t remember the last time you
changed the seal, just replace it now.
D25F Troubleshooting - Part 1

Page 5
800-523-8499
www.dosatronusa.com
Proper protection, such as gloves, eye wear, and aprons, are recommended when disassembling a Dosatron.
Step 14: Replace the lid, hand tight. Your Medicator should now
be drawing the concentrate.
Step 13: Carefully, insert the piston into the body.
D25F Troubleshooting - Part 1 D25F Troubleshooting - Part 1

Page 6
800-523-8499
www.dosatronusa.com
Proper protection, such as gloves, eye wear, and aprons, are recommended when disassembling a Dosatron.
Step 3: Unscrew and remove the check valve barb.
Step 2: Remove the suction hose.
D25F Troubleshooting - Part 2
If your Medicator is pushing water down into the stock solution
tank, it’s time to investigate the check valve.
Step 1: To do this, remove the hose nut.
This D25F Troubleshooting will cover: The Medicator is pushing water down into your stock
solution tank, but is clicking.

Page 7
800-523-8499
www.dosatronusa.com
Proper protection, such as gloves, eye wear, and aprons, are recommended when disassembling a Dosatron.
D25F Troubleshooting - Part 2
Step 6: Inspect the seal (Part #: J051) and the check valve
assembly (Part #: MPDI122). If they are dirty, you may be able to
soak, brush off, and reinstall. If you see damage or if you don’t
remember the last time you changed these parts, just replace
them now.
Step 5: Then carefully pry the check valve assembly down and out
of the stem. A small at blade screwdriver or pick will make this
easier.
Step 4: Remove the check valve seal (Part #: J051).

Page 8
D25F Troubleshooting - Part 2
Step 8: Place the check valve seal with the groove facing upward
into the new barb.
Step 9: Thread it onto the white stem and hand-tighten.
800-523-8499
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Proper protection, such as gloves, eye wear, and aprons, are recommended when disassembling a Dosatron.
Step 7: To reassemble, press the new check valve assembly into
the stem as far as it will go.

Page 9
D25F Troubleshooting - Part 2
Step 11: Slide it onto the barb.
Step 12: Hand tighten the nut. This should stop the water from
dripping back into the stock tank.
800-523-8499
www.dosatronusa.com
Proper protection, such as gloves, eye wear, and aprons, are recommended when disassembling a Dosatron.
Step 10: Thread the suction hose nut onto the hose.

Page 10
D25F Troubleshooting - Part 3
Step 2: Grasp the white valve support and pull the piston straight
out of the body. Set the body aside.
Step 3: Inspect the white valve support on the top.
800-523-8499
www.dosatronusa.com
Proper protection, such as gloves, eye wear, and aprons, are recommended when disassembling a Dosatron.
Step 1: If the Medicator isn’t clicking, unscrew and remove the lid.
If it is tight, just use the strap wrench (Part #: TOOL01) to loosen
it. Set the lid aside.
This D25F Troubleshooting will cover: The Medicator is not clicking.

Page 11
D25F Troubleshooting - Part 3
Step 5: Check the two actuator springs (Part #: M238) on the
bottom. If they are broken or missing, just replace them.
Step 6: You can check the piston shell by inspecting the upper
and lower anges. If they are worn or have deep scratches, the
piston shell (Part #: P421) needs to be replaced. Also, check the
piston shell’s t inside the body. To do this, invert the piston and
slide it into the body. It should be a snug t. If it feels loose, the
piston shell and push rod o-ring needs to be replaced.
800-523-8499
www.dosatronusa.com
Proper protection, such as gloves, eye wear, and aprons, are recommended when disassembling a Dosatron.
Step 4: Press the pushrod down.

Page 12
D25F Troubleshooting - Part 3
Step 8: Press the pushrod up.
Step 9: Slide the valve support off the inlet valve and set aside.
800-523-8499
www.dosatronusa.com
Proper protection, such as gloves, eye wear, and aprons, are recommended when disassembling a Dosatron.
Step 7: To replace the piston shell, use a small tip Phillips
screwdriver and remove the valve support screw and plastic
retainer.

Page 13
D25F Troubleshooting - Part 3
Step 11: Pull the actuator assembly out and discard the old piston
shell.
Step 12: Put the new push rod o-ring (Part #: J020) on top of the
push rod and slide it down as far as it will go.
800-523-8499
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Proper protection, such as gloves, eye wear, and aprons, are recommended when disassembling a Dosatron.
Step 10: Next, remove the four screws in the center of the piston
shell to release the actuator assembly.

Page 14
D25F Troubleshooting - Part 3
Step 14: Now re-install the four screws and hand tighten them in a
star pattern.
Step 15: Press the white plastic portion of the actuator side to
side. If there is movement, re-tighten the screws.
800-523-8499
www.dosatronusa.com
Proper protection, such as gloves, eye wear, and aprons, are recommended when disassembling a Dosatron.
Step 13: Then, position the actuator assembly in the shell as
shown and hold rmly.

Page 15
D25F Troubleshooting - Part 3
Step 17: Next, position the retainer and hand tighten the screw.
Step 18: Test the piston, by pressing the pushrod from the top and
bottom, it should click each time.
800-523-8499
www.dosatronusa.com
Proper protection, such as gloves, eye wear, and aprons, are recommended when disassembling a Dosatron.
Step 16: If there is no movement, reinstall the valve support by
sliding it onto the inlet valve.

Page 16
D25F Troubleshooting - Part 3
Step 20: Hand tighten the lid. Your Medicator should now be
clicking and drawing concentrate.
800-523-8499
www.dosatronusa.com
Proper protection, such as gloves, eye wear, and aprons, are recommended when disassembling a Dosatron.
To learn more, scan the QR codes below for more information.
Step 19: Insert the piston back into the blue body.
Scan the
QR code
to go to
Dosatron’s
video
page.
Scan the
QR code
to go to
Dosatron’s
YouTube
Channel.