3
60-2242—2
T921A,B,E-G
SPECIFICATIONS
Fig. 1—T921 approximate installation dimen-
sions in in. [mm].
SETTING
ADJUSTMENT
KNOB
1
1
M9107
3
[84]
5
16
5
[145]
11
16
5
[137]
3
8
7
[194]
5
8
1
16
3 [78]
5
16
3 [84]
3
8
3 [86]
5
16
5 [135]
1
4
2 [57]
FOR VERTICAL
CONDUIT BOX (2)
HORIZONTAL CONDUIT BOX
ACCESSORY ADAPTER PLATE (127246A) FOR
MOUNTING ON HORIZONTAL CONDUIT BOX
2-11/16 [69] INCHES FOR
T921F, G MODELS.
7640HX Averaging Element Mounting Kit: For mount-
ing in existing installations where access to the duct
is impractical.
Q615A Enclosure: To protect the device when mounted
outside; splash proof.
801534 Calibration Wrench.
107324A Bulb Holder: For mounting the bulb in a duct.
34886A Outdoor Bulb Shield: To protect the outdoor
bulb mounting.
Fig. 2—T991B approximate installation
dimensions in in. [mm].
TABLE 1—ACCESSORY FACEPLATE.
Scale
Part No.
56
°
to 84
°
F [13
°
to 29
°
C]
135135A
13
°
to 29
°
C [56
°
to 84
°
F]
135135B
42
°
to 75
°
F [5
°
to 24
°
C]
135135C
66
°
to 95
°
F [19
°
to 35
°
C]
135135D
56
°
to 84
°
F [13
°
to 29
°
C]
135135C
a
a
Blank faceplate.
REPLACEMENT PART:
130224 Locking Cover Knob.
OPTIONAL SPECIFICATION (USING THE T991B):
Alternate proportional control similar to the T921A, but
uses an outdoor temperature, automatic control point
reset.
T991B with 3-1/2: 1 reset and 50
°
to 120
°
F [10
°
to
49
°
C] temperature setting scale (when the outdoor
bulb is at 60
°
F [16
°
C]).
DIMENSIONS:
Refer to Fig. 2.
ACCESSORIES:
Compression fittings, immersion wells: Refer to the
appropriate specification or the TRADELINE
®
Cata-
log.
314439 Mounting Clips: For mounting a capillary tub-
ing (averaging element) in a duct.
1
1
2
2
3
3
M9108
4
[106]
3
16
[10]
DIAMETER
3
8
5
[143]
5
8
[24]
1
4
1
[32]
1
8
2 [57]
1
4
4 [108]
1
4
2 [57]
7
32
[6]
DIAMETER (3)
3
4
1
[45]
OUTDOOR BULB SIZE VARIES INVERSELY WITH THE RESET RATIO.
INDOOR BULB LENGTH AND DIAMETER IS 4-1/2 [114] INCH BY
1/2 [13] INCH EXCEPT FOR THE AVERAGING ELEMENT WHICH IS
1/8 [3] INCH DIAMETER BY 12 FT. [3 M] LONG.
CLEARANCE NECESSARY TO REMOVE COVER.
15
16
[24]
15
16
[10]
3
8
2 [51]
KNOCKOUT FOR 1/2 INCH
CONDUIT (BOTH ENDS)
