Cashco 764T Temperature Controller - Manual (Page 8)

IOM- 764T 8
11.
12.
13.
14.
15.
16.
17.
18.
Pick up housing (1). Using a suitable screw-
driv er, rotate needle valve (3) CW until it
seats. Keep track of the number of rev o lu-
tions required to seat the nee dle valve (3) and
record in table below:
Number of revolutions required to seat the
needle valve: _____
Reverse the rotation of the needle valve (3)
and fully remove. Remove needle valve
O-ring (7).
Solvent clean and air blow all internal parts.
Install new O-rings on the needle valve (7),
and three on sensor (5).
Place thermal bulb (12) back into a vise. Insert
Invar rod (13) (also extension post (14)) into
thermal bulb (12).
Re-assemble sensor subassembly (2) end
plate (2.2), adjusting screw (2.3), and sensor
(2.1) per the recorded number of revolutions
of Step 10, this sub-section; this will give
"preliminary" adjustment. See Figure 9 for
"fi nal" adjustment dimensions of the sensor
subassembly (2). Rotate sensor (2.1) as
required to the closest hole avail able to allow
sensor pin (2.4) to be in sert ed; insert pin (2.4).
2. (cont.)
Remove name plate (10) by re mov ing screw
(9).
Remove four sensor end plate screws (8).
Grasp sensor end plate (2.2) and with draw
vertically from housing (1). Lay sensor sub as-
sem bly (see Figure 9) on work surface; take
care to not lose sensor pin (2.4) in han dling.
3.
4.
7.
6. Hand-grasp housing (1) and rotate CCW
(viewed from knob end) to removal. Keep
track of the number of revolutions to removal
in table of Step 2, previous. Take care not to
invert and drop the sensor plate subassembly
(15) from the housing (1) internals in han dling.
Remove thermal bulb (12) from vise, taking
care not to invert and drop Invar rod (13) (also
extension post (14)) of the thermal bulb (12)
and cause end damage to rod (13) (also post
(14)). Examine bulb (12) interior for signs of
leakage; recommend complete 764T re place-
ment if leakage is discovered.
Holding the housing (1) in a vise, remove the
sensor plate O-ring (6) using an awl-type tool,
and discard. DO NOT DAMAGE METAL
SURFACES!
Remove the housing (1) from the vise, invert
housing (1) with hand covering knob-end to
allow sensor plate subassembly (15) to drop/
slide out of the housing (1); it may be nec es sary
to push adapter (15.2) to remove the sen sor
plate subassembly (15).
Pick up sensor subassembly (2). Allow sen sor
pin (2.4) to be removed. Rotate sensor (2.1)
CCW (viewed from sensor end) to re mov al.
Keep track of the number of rotations to re move
the sensor (2.1) from the ad just ing screw (2.3)
in the following table:
Rotate sensor end plate (2.2) CCW (viewed
from sensor end) to removal. Keep track of
the number of rotations to remove the end
plate (2.2) from the ad just ing screw (2.3) in
the table of Step 11.
Remove three O-rings (5) from sensor (2.1).
8.
5.
Number of revolutions to remove sen sor
from ad just ing screw: ______
Number of revolutions to remove sen sor
end plate from adjusting screw: ______
10.
9.
Number of revolutions lock nut is "loos-
ened" from thermal bulb: ______
Number of revolutions to remove hous ing
from thermal bulb: ______
(NOTE: A tem po rary piece of tape may be
used to cover the hole the pin is inserted into,
to prevent the pin from becoming lost.)
Figure 9: Sensor Sub-Assembly Dimensions