14
6.3.2. Accessing the Sensor Assembly
The loading mechanism and vent seat for the LF-691 can be accessed from the top of the regulator. Ensure
the spring is de-compressed by rotating the T-Bar fully anti-clockwise and follow the instructions below:
i.
Remove the T-Bar (32, 33) by unscrewing one side whilst firmly gripping the other.
ii.
With the regulator secured up-right in a vice, remove the bonnet (31) by using a torque wrench
or equivalent with 47mm open end.
iii.
Un-screw and lift the top works from the assembly, inclusive of the bonnet (31), load spring
(15), adjusting mechanism (16, 17, 18 & 19) and lower spring rest (12) from the body.
iv.
The sensor assembly (10, 11, 13 & 14) can be removed from the body by using an M5 bolt
(supplied with kit) and pliers.
v.
If necessary, the baffle plate (3) and connector (8) can be withdrawn. Inspect the connector for
damage and replace if required.
vi.
The vent seat (14) can be accessed by removing the sensor (10) from the sensor holder (11) and
gripping the sensor firmly in a vice with the vent seat nut (13) facing upwards.
vii.
The vent seat nut (13) can be removed using a 10mm open ended spanner and the vent seat
(14) can then be removed from the sensor (10) along with the 6.85mm x 2mm ‘O’
ring (22).
viii.
Inspect the vent seat (14) for damage and replace if necessary.
ix.
Replace all ‘O’ rings (21, 22, 23, 24, 29 & 30) located on the sensor (10) and sensor holder (11)
prior to reassembly, ensuring adequate lubrication is used.
x.
Place the connector (8) into the baffle plate (3) and locate into the regulator body, taking care
not to damage the sealing edge of the connector.
xi.
After reassembling the sensor (10) and holder (11), place the assembly into the regulator body
(1) ensuring that it is firmly in place.
xii.
Remove the M5 screw from the sensor holder if used.
xiii.
Screw the top works onto the regulator body and using a torque wrench, tighten to 120Nm.
xiv.
Tighten the securing grub screw (20) against the bonnet (31).
xv.
Place the T-Bar piece with the male thread (32) through the hole on the adjusting screw and
tighten the second T-Bar piece (33) against it.
It is recommended that all parts in the repair kits are used. Any defect parts removed during the service
should be disposed of.
Replacement
‘O’ rings
should be lubricated with suitable non-hydrocarbon grease such as Krytox GPL205.
