Lancaster 7-LXDAN-1B, Installation, Operating And Service Manual

PAGE 28

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. 
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. Rotate the motor at least a 

¼ 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 motor 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 maintenance involving the drive assembly or the drive cap assembly and pistons, 
unplug power source jack from the printed circuit board (black wire) and plug back in or press and hold 

NEXT

 and 

REGEN

 buttons for 3 

seconds.
This resets the electronics and establishes the service piston position. The display should flash the software version and then reset the 

valve to the service position. 

DRIVE CAP ASSEMBLY, MAIN PISTON AND REGENERANT PISTON (refer to page 19&20 for diagrams):

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 service spanner wrench (see page 16) or insert a ¼” to ½” 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 below. The notches are visible through the holes. Lever the screwdriver so the drive cap assembly 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 spline, 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 a regenerant piston for 7-LXCTAIR, 7-LXIMAIR, 7-LXKATAIR,and 7-LXKATAIRO3 models).
The regenerant piston (the small diameter one behind the main piston found only on the 7-LXCTAIR, 7-LXIMAIR, 7-LXKATAIR and 

7-LXKATAIRO3 models) is removed from the main piston by pressing sideways and unsnapping it from its latch. Chemically clean in 

dilute sodium bisulfite or vinegar, or replace the regenerant piston if needed. To remove the main piston fully extend the piston rod 

and then unsnap the main piston from its latch by pressing on the side with the number. Chemically clean in dilute sodium bisulfite or 

vinegar, or replace the main piston.
Reattach the main piston to the drive cap assembly. Reattach the regenerant piston (if needed) to the main piston. Reinsert the drive 

cap assembly and piston into the spacer stack assembly and hand tighten the drive cap assembly. Continue to tighten the drive cap 

assembly using a screwdriver as a ratchet until the black o-ring on the spacer stack assembly is no longer visible through the drain port. 

Excessive force can break the notches molded into the drive back plate. Make certain that the main drive gear still turns freely. The 

exact position of the piston is not important as long as the main drive gear turns freely.
Reattach the drive assembly to the control valve and connect all plugs. After completing any valve maintenance involving the drive 

assembly or the drive cap assembly and pistons, unplug power source jack from the printed circuit board (black wire) and plug back in 
or press and hold 

NEXT

 and 

REGEN

 buttons for 3 seconds.

This resets the electronics and establishes the service piston position. The display should flash the software version and then reset the 

valve to the service position.