BAPI Immersion Temperature Transmitters Catalog Page

20918_ins_Immersion_Active

Overview and Identication

The BA/#-I Immersion temperature transmitter is
made for thermowell mounting and measurement
in water pipes, water tanks or cooling tower sump
applications. The Stainless Steel probe is made in
different lengths for a custom thermowell t.

Fig 2:

Junction Box

(JB)

Immersion Temperature Transmitters

BA/#-I

Fig 1: BAPI-Box (BB)

Fig 3: Weather Tight (EU)

Temperature Transmitter

Installation & Operations

rev. 06/30/15

Fig 4:

BAPI-Box 2

(BB2)

Thermowell Installation

BAPI’s immersion probes are designed to be
installed in a thermowell. to install a thermowell,
a pipe tter typically drills a ¾-inch hole into the
pipe where the thermowell is needed. A customer­provided tting, called a Threadolet or Weldolet, is
welded to the pipe over the hole. The Threadolet
has a ½” NPT thread in the center. Thread sealant
such as Teon tape or pipe dope is applied to the ½”
NPT threads of the thermowell. The thermowell is
then inserted into the Threadolet and tightened.

Figure 6 shows a 4” thermowell and 4” immersion
probe installed into 12” pipe. Usually thermowells
are sized to extend to the center of the pipe;
however, shorter thermowells will give proper
temperature readings if properly installed.

Since the wall thickness of the pipe commonly used
for HVAC plumbing is ½-inch, the thermowell sticks
four inches into the pipe. The four-inch distance
called out by a four-inch thermowell is the distance
from the inside surface of the pipe to the end of the
thermowell.

Fig 5:

Weatherproof

(WP)

6.5” Overall
Probe Length

Threadolet

2” Thick
Pipe Insulation

1/2” Thick
Pipe Wall
(Schedule 80)

4” Thermowell

Insertion Length

Fig 6: Typical

Immersion Probe

Installed in a

Thermowell.

Weld

Specications subject to change without notice.

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Immersion Temperature Transmitters

BA/#-I

20918_ins_Immersion_Active

Immersion Sensor Installation

Immersion probes come with a plastic tting that screws into the threads at the top of the thermowell. Pull the probe away
from the plastic tting until the probe is fullly extended. Insert the immersion probe into the thermowell until the plastic
ttings come into contact with the threads in the thermowell. Hand tighten the immersion sensor snugly into the
thermowell without too much torque. The unit is designed so that the temperature probe slides back into the enclosure as
the sensor contacts the bottom of the thermowell. Make sure that the tip of the immersion sensor probe is in good contact
with the bottom of the thermowell by pushing on the aired end of the probe until the tip bottoms out in the thermowell.

Length Per Order
*Sensor Slides

1. Pull Probe to
Extend Fully

2. Insert

3. Hand Tighten

Fig 7: Immersion Sensor Before Insertion

*As the immersion sensor is hand threaded into the
thermowell, the air end of the probe will be pushed back
into the enclosure as the probe tip bottoms out in the
thermowell. The probe can slide up to 1.6”. The Junction
Box enclosure is shown above but the process is the
same for the other enclosure styles.

Fig 8: Immersion sensor after insertion into
the thermowell.

(Junction box enclosure shown above.)

Temperature Transmitter

Installation & Operations

rev. 06/30/15

Hand tighten
immersion probe
threads into the
thermowell

Installation in Pipes Less than 3” in Diameter

T- Mount

Figure 9 shows how a 2” Tee and a 1/2” to 2” bushing allows a 2” thermowell to measure the temperature of the contents
of a 2” water pipe. Be sure to use a thread sealant on the outside threads of the thermowell.

Corner Mount

Figure 5 shows how a pipe Tee can be used in an elbow application. A 2” tee and a 1/2” to 2” bushing allows a 4”
thermowell to measure the temperature of the contents of a 2” water pipe.

Note: Temperatures in pipes as small as 1-1/4” may be measured by this method. In small pipes, the diameter of the
thermowell may become a signicant obstruction, so be sure to check for proper ow rates after installation is complete.

T-Pipe Fitting

Reducer

1/2 Inch NPT

1/2 Inch NPT

Reducer

T-Pipe Fitting

Fig 9: Typical T-Mount

Fig 10: Typical Corner Mount

Specications subject to change without notice.

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