IMMERSION WELLS AND COMPRESSION FITTINGS
68-0040—04 10
Fig. 6. Mounting spring clip into well spud.
Securing Bulb in Wells with Setscrew
Wells with a spud setscrew are designed for use with
controllers that have armored capillary with a brass collar at
the bulb end of the armor. The setscrew tightens against the
brass collar. See Fig. 7. These wells can be adapted for use
with 5/64 in. capillary by adding the 124904 Well Adapter and
the 121371 Mounting Clamp Assembly. See Fig. 3.
Fig. 7. Mounting armored capillary in well with setscrew.
Capillary Compression Fittings
1. Coat external spud threads with a moderate amount of
pipe dope, leaving two end threads bare. See Fig. 4.
NOTE: Teflon tape can also be used.
2. Screw the spud into the tapping and tighten securely.
3. Place the packing nut on the tubing.
4. Slide the bulb completely through the fitting.
5. Place the composition disk and the four slotted brass
washers on the tubing in the order shown in Fig. 8.
6. Turn the brass washers so that the slots are 180 degrees
apart and the small tabs are in the mating slots.
7. Slide the seal assembly into the fitting. Make sure the
sensing bulb extends the desired distance into the
controlled medium. See Fig. 2.
8. Tighten the packing nut.
Fig. 8. Capillary compression fitting assembly.
Element Holders
Use element holders to mount air temperature sensors in a
duct. Locate the sensing element where air at representative
temperatures can circulate around it. In a plenum application,
locate the element far enough from the combustion chamber to
avoid the effect of direct radiation.
Bulb Holders
1. Cut a hole large enough to admit the bulb and holder in
the duct or plenum at the mounting location.
2. Drill holes for the bulb holder mounting screws.
3. Mount the bulb and capillary on the holder. See Fig. 9
through 11.

107324A and 131524A Bulb Holders

Use these bulb holders to mount one bulb in a duct or plenum.
See Fig. 9 and 10. If necessary, shorten holders by using pliers
to flex the channel at one of the notches until it separates.

311266D Bulb Holder

Use this bulb holder to mount one or two bulbs in a duct where
temperatures do not exceed 100°F (38°C). The removable
plug in the mounting plate allows insertion of a thermometer to
check duct air temperature. See Fig. 11 for installation details.
Fig. 9. Installing capillary in 107324A
and 131524A Bulb Holders.
Fig. 10. Mounting bulb holder in furnace plenum.
M17263
BULB
INSERTION LENGTH
APPROX. 3-3/8 IN.
TUBING SPRING CLIP
FITTING (INCLUDING WELL)
M17264
1/2 in. (13 mm) PIPE THREAD FOR 1/2 in. (13 mm) CAPSULES
3/4 in. (19 mm) PIPE THREAD FOR 11/16 in. (17 mm) CAPSULES
COMPOSITION DISK
(SLOTTED)
SPUD
CAPILLARY TUBING
SLOTTED WASHERS
ASSEMBLED IN PAIRS
THUS-
PACKING NUT
M17258
PINCH TOP EDGES OF
HOLDER TOGETHER
AT EACH SEGMENT
CAPILLARY
TUBING
SENSING
BULB
BE SURE EXTENSION TUBE IS
UNDER BULB HOLDER, AS SHOWN
M7217
M17265
CAPILLARY
TUBING
SCREW
HOLES IN
WALL OF
PLENUM
INDOOR
BULB
COMBUSTION CHAMBER
KEEP BULB WELL ABOVE COMBUSTION CHAMBER