tekmar 256 Boiler Control User Manual
Page 11
Mounting the Universal Sensor
Note: This sensor is designed to mount on a pipe or in a temperature
immersion well.
The Universal Sensor should be placed downstream of a pump or
after an elbow or similar fi tting. This is especially important if large
diameter pipes are used as the thermal stratifi cation within the pipe
can result in erroneous sensor readings. Proper sensor location
requires that the fl uid is thoroughly mixed within the pipe before it
reaches the sensor.
Strapped to Pipe
The Universal Sensor can be strapped directly to the pipe using the
cable tie provided. Insulation should be placed around the sensor to
reduce the effect of air currents on the sensor measurement.
Immersion Well
If a Universal Sensor is mounted onto 1” (25 mm) diameter L
type copper pipe, there is approximately an 8 second delay
between a sudden change in water temperature and the time the
sensor measures the temperature change. This delay increases
considerably when mild steel (black iron) pipe is used. In general,
it is recommended that a temperature well be used for steel pipe
of diameter greater than 1-1/4” (32 mm). Temperature wells are
also recommended when large diameter pipes are used and fl uid
stratifi cation is present
.
Conduit Connection
The Universal Sensor and Universal Sensor Enclosure 080 (sold
separately) are specifi cally designed to mount onto a 3/8” (10 mm)
ID temperature well that is supplied with an end groove. To install
the well, plumb a ‘T’ into the pipe and fi x the well into the ‘T’. The 080
enclosure has a 7/8” (22 mm) back knockout that must be removed
and fi tted over the temperature well. The sensor is then inserted
into the well and the retaining clip supplied with the enclosure is
snapped onto the well end groove. If the well has a threaded end,
the installer must supply a standard threaded conduit retaining ring.
The two wires from the sensor are connected to the terminal block
provided in the enclosure. The other side of the terminal block is
used to connect wires from the control.
Bottom of
Enclosure 080
Universal
Sensor
Cable Tie
Sensor Well
Retaining Clip
Universal
Sensor
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© 2011
D 256 - 07/11