Service Instructions - Hellenbrand H-125 Series Owner's Manual

Drive Assembly
Remove the valve cover to access the drive assembly.
Disconnect the power source plug (black wire) from the PC
board prior to disconnecting the motor or water meter plugs
from the PC board. The power source plug connects to the
four-pin jack. The motor plug connects to the two-pin jack
on the left-hand side of the PC board. The water meter plug
(gray wire) connects to the three-pin jack on the far right-hand
side of the PC board.
PC Board Replacement
The PC board can be removed separately from the drive
bracket but it is not recommended. Do not attempt to remove
the display panel from the PC board. Handle the board by
the edges. To remove the PC board from the drive bracket,
unplug the power, water meter and motor plugs from the PC
board. Lift the middle latch along the top of the drive bracket
while pulling outward on the top of the PC board. The drive
bracket has two plastic pins that fit into the holes on the lower
edge of the PC board. Once the PC board is tilted about 45º
from the drive bracket it can be lifted off of these pins. To
reinstall a board, push the top of the PC board towards the
valve until it snaps under the middle latch, weave the power
and water meter wires into the holders and reconnect the mo-
tor, water meter and power plugs.
Drive Bracket Replacement
The drive bracket must be removed to access the drive
cap assembly and pistons or the drive gear cover. It is not
necessary to remove the PC board from the drive bracket to
remove the drive bracket. To remove the drive bracket start
by removing the plugs for the power source and the water me-
ter. Unweave the wires from the side holders. Two tabs on
the top of the drive back plate hold the drive bracket in place.
Simultaneously lift the two tabs and gently ease the top of the
drive bracket forward. The lower edge of the drive bracket
has two notches that rest on the drive back plate. Lift up and
outward on the drive bracket to disengage the notches.
To reassemble, seat the bottom of the drive bracket so the
notches are engaged at the bottom of the drive back plate.
Push the top of the drive bracket toward the two latches. The
drive bracket may have to be lifted slightly to let the threaded
piston rod pass through the hole in the drive bracket. Main-
tain a slight engaging force on top of the drive bracket while
deflecting the bracket slightly to the left by pressing on the
side of the upper right corner. This helps the drive gears
mesh with the drive cap assembly. The drive bracket is
properly seated when it snaps under the latches on the drive
back plate. If resistance is felt before latching, then notches
are not fully engaged, the piston rod is not in hold, the wires
are jammed between the drive bracket and drive back plate,
or the gear is not engaging the drive cap assembly.
Drive Gear Replacement
To inspect the drive gears, the drive gear cover needs to be
removed. Before trying to remove the gear cover, the drive
bracket must be removed from the drive back plate. (Refer to
the instructions above regarding removing the drive bracket
from the drive back plate. The drive gear cover can be
removed from the drive bracket without removing the motor
or the PC board.) The drive gear cover is held in place on the
drive bracket by three clips. The largest of the three clips is
always orientated to the bottom of the drive bracket. With the
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SERVICE INSTRUCTIONS

PC board facing up, push in and down on the large clip on the
drive gear cover. Handle the cover and the gears carefully so
that the gears do not fall off the pegs in the cover.
Replace broken or damaged drive gears. Do not lubricate
any of the gears. Avoid getting any foreign matter on the
reflective coating because dirt or oils may interfere with pulse
counting.
The drive gear cover only fits on one way, with the large clip
orientated towards the bottom. If all three clips are outside of
the gear shroud on the drive bracket the drive gear cover slips
easily into place.
Drive Motor Replacement
The drive bracket does not need to be removed from the drive
plate if the motor needs to be removed. To remove the motor,
disconnect the power and motor plugs from the jacks on the
PC board. Move the spring clip loop to the right and hold. Ro-
tate the motor at least a 1/4 turn in either direction so the wires
are vertical (up & down) before gently pulling on the wire
connectors to remove the motor. Pulling directly on the wires
without rotating the motor may break the wires off the motor.
Replace the motor if necessary. Do not lubricate the motor
or the gears. To reinstall the motor, move the spring clip loop
to the right and hold. Gently turn the motor while inserting so
that the gear on the motor meshes with the gears under the
drive gear cover. Release the spring clip loop and continue
to rotate the motor until the wires are horizontal and the mo-
tor housing engages the small plastic bulge inside the drive
bracket motor retainer. Reconnect the motor plug to the
two-pronged jack on the lower left side of the PC board. If
the motor will not easily engage with the drive gears when
reinstalling, lift and slightly rotate the motor before reinserting.
Reconnect the power plug.
Replace the valve cover. After completing any valve main-
tenance, press and hold NEXT and REGEN buttons for 3
seconds or unplug power source jack (black wire) and plug
back in. This resets the electronics and establishes the
service piston position. The display should flash all wording,
then flash the software version and then reset the valve to the
service position.
Drive Cap Assembly, Main Piston and Regenerant Piston
The drive assembly must be removed to access the drive
cap assembly. The drive cap assembly must be removed to
access the piston(s). The drive cap assembly is threaded into
the control valve body and seals with an o-ring. To remove
the drive cap assembly use the special plastic wrench or
insert a 1/4" to 1/2" flat blade screwdriver into one of the slots
around the top 2" of the drive cap assembly so it engages the
notches molded into the drive back plate around the top 2"
of the piston cavity. See Figure 29. The notches are visible
through the holes. Lever the screwdriver so the drive cap as-
sembly turns counter clockwise. Once loosened, unscrew the
drive cap assembly by hand and pull straight out.
The drive cap assembly contains the drive cap, the main drive
gear, drive cap, piston rod and various other parts that should
not be dissembled in the field. The only replaceable part on
the drive cap assembly is the o-ring. Attached to the drive
cap assembly is the main piston and if a regenerant is used, a
regenerant piston.