Troubleshooting for D25 Series
Symptom Cause
Solution
Piston
Piston is not clicking
The unit is installed in the wrong
direction
The arrow on the unit should point in the same
direction as the water flow. Water supply and
demand valves should be open.
Piston locked up/not clicking
Reset piston. See instructions.
Broken actuator spring
Replaced both actuator springs.
Excessive water flow
1. Reduce the flow rate and slowly restart the
unit.
2. Remove the lid, pull out the piston and check
if the O-rings around the piston valves are
missing or dislodged.
3. Reset piston (see instructions) screw lid back
on.
Water hammer
Reset piston (see instructions) and install water
hammer arrestor in the appropriate location.
In-line water filter is clogged
Clean the in line water filter.
Worn, scratched/scored piston shell and/
or body
Do piston “fit” test (see instructions). replace
piston shell and/or body. Make sure your
installation has a 200 mesh filter before the
Dosatron.
Dosing
Water flowing back into
solution container
Check valve dirty, worn, assembled
incorrectly or missing.
Clean or replace the check valve assembly. Be
sure the check valve seal is in proper position.
No suction of solution
Piston locked up/not clicking
Reset piston. See instructions.
Air leak in the suction tube
Check suction tube connection. Inspect suction
tube for pin holes or cracks.
Check tightness of connection nuts.
Cut ½” of top of the hose and reattach it
correctly.
Suction tube or strainer clogged
Clean suction tube and strainer or replace hose
assembly.
Raise strainer 2” off the bottom of stock tank
solution.
Check valve worn, improperly
assembled, dirty or damaged
Clean or replace check valve assembly. Be sure
the check valve seal is in proper position.
Plunger seal is damaged, swollen or
missing
Clean or replace plunger seal.
If plunger seal is missing, check incoming water
pressure; refer to unit manual for specifications.
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