Honeywell 121371B Product Data page 11

3 - 1
/ 4
( 8 3
1 - 3 )
/ 8
( 3 5
)
3 - 1
1 - 5
/ 4
( 8 3 / 8
( 4 1
)
)
2 - 3
/ 4
( 7 0
)
ACCESS
HOLE
RUBBER GROMET
NO. 8 SHEET METAL
MOUNTING SCREWS (2)
Fig. 11. Mounting sensing bulb and
311266D Bulb Holder in duct.
NOTE: Dimensions shown in in. (mm).
Duct Mounting with Capillary Compression
Fitting
In some duct-mount application, it is desirable to use a
compression fitting to reduce air leakage at the sensing
element location. For these applications, first mount a waste
nut on the duct to ensure secure mounting. See Fig. 12. See
Table 6 for part numbers.
NOTE: Do not use this mounting method for liquid
applications.
WASTE DUCT
NUT WALL
CAPILLARY CAPILLARY
TUBING
COMPRESSION
FITTING
Fig. 12. Mounting sensing bulb in duct using waste nut
and compression fitting.
Averaging Element Holders
The averaging element must be supported so it is distributed
evenly across the entire height and width of the duct. It can be
fastened to perforated strap iron (see Fig. 13) or mounted with
314439 Mounting Clips (see Fig. 14). This type of mounting
requires threading the element through a grommet inserted in
a hole in the duct wall.
For ducts with limited access, the 7640HX Averaging Element
Mounting Kit allows mounting the element through a single
hole in the side of the duct. This kit requires a length of 1/2 in.
EMT conduit. See Fig. 15.
THERMOMETER
BULB
6 )
( 3 5
1 4
ADJUSTABLE
SPRING
CLIPS (2)
CONTROLLER BULB
2-1/4 x 2-1/4 (57 x 57) APPROXIMATE
HOLE IN DUCT FOR INSTALLATION
M7355
BULB
(CAPSULE)
M17266
IMMERSION WELLS AND COMPRESSION FITTINGS
CAPILLARY
TUBING
GROMMET
DUCT
WALL
Fig. 13. Mounting averaging element with
CAPILLARY
TUBING
GROMMET
DUCT
WALL
Fig. 14. Mounting averaging element with
314439 Mounting Clips.
GROMMET
WIRE TIES
CAPILLARY
CONDUIT
COMPRESSION
FITTING
4 in.
COVER
PLATE
DUCT
WALL
M17270
Fig. 15. Mounting averaging element with 7640HX
Averaging Element Mounting Kit.
11
WIRE FASTENINGS
perforated strap iron.
AVERAGING
ELEMENT
USE NO. 10
SHEETMETAL
SCREWS
314439
CLIP
BEND HERE
IF NECESSARY
1/2 in. EMT CONDUIT
(OBTAIN LOCALLY)
AVERAGING
ELEMENT
ELEMENT
M17269
M17289
68-0040—04