tekmar 521 Programmable Thermostat Installation - Manual (Page 7)

© 2014 521_D - 01/14
7 of 28 A Watts Water Technologies Company
Tile Floor Coverings
If a Slab Sensor 079 is to be installed into an existing tile floor with sufficiently large
grout lines, the sensor and wire can be installed in one of the grout lines between the
tiles. Select a low traffic area of the floor that is mid way between the heating elements
for the sensor location. Ensure that the sensor is located in such a position that the
attached wire is able to reach to a suitable junction location. Splices within the grout
should be avoided to ensure trouble free operation. Remove the appropriate grout line
and place the sensor and wire in the floor. Re-grout the area.
Installing the Sensor to the Bottom of a Subfloor
If the sensor is to be installed to the bottom of a subfloor, cut a piece of 1" (25 mm)
thick rigid insulation into a 6" (150 mm) by 6" (150 mm) square. A groove 3/16" (5 mm)
wide by 3/16" (5 mm) deep by 1-3/4" (45 mm) long should be cut into the insulation to
accommodate the sensor. Place the sensor in the groove and sandwich the sensor
between the insulation and the subfloor. Use a suitable fastening method to affix the
insulation to the subfloor.
Retrofit Installations ------------------------------------------------ ------------------------------------------------
The Slab Sensor 079 is supplied with 10' (3 m) of cable. If a longer length is
required, 24 AWG or larger wire can be spliced onto the two wires from the sensor.
The splices should be properly soldered and protected in an accessible junction
box. Follow the sensor testing instructions given in this brochure and then connect
the wires to the control.
Slab Sensor 079 Wiring
Do not run sensor wires parallel to telephone or power cables. If the sensor
wires are located in an area with strong sources of electromagnetic interference,
shielded cable or twisted pair should be used or the wires can be run in a grounded
metal conduit.