1 (3)
1
a
b
c
d
2
3
4
Connection diagram with LK Actua-
tor normally closed (NC)
Sensor
Relay
250 V AC
8(2)A
DC
AC
LK Actuator 24V AC (NC) 2W
LK Transformer 230/24V AC 60VA
24V AC
230V AC
N
L
230V AC
N
L
Connection diagram with LK Actua-
tor normally open (NO)
Sensor
Relay
250 V AC
8(2)A
DC
AC
LK Actuator 24V AC (NO) 2W
LK Transformer 230/24V AC 60VA
24V AC
230V AC
N
L
230V AC
N
L
Design
The LK Electronic Thermostat TR 26 is designed
for under floor heating installations in particular-
ly demanding environments such as industrial
and agricultural wash down areas. The thermo-
stat is used with sensors for regulating floor or air
temperature. Up to 10 LK 24V AC actuators or 8
LK 24V AC manifold actuators can be controlled
from the TR26. Out put is from a 230v/24v trans-
former. The thermostat must fully enclosed by
the LK Thermostat Housing. We recommend the
housing is located next to the manifold or other
suitable location.
Floor temperature regulation
TR26 is used with LK Floor Sensor FK133/4,
length 4M. The sensor can be extended as shown
in the table below. The floor sensor should be en-
capsulated in conduit between two under floor
heating pipes and in a location representative of
the entire floor surface. If overall temperature
regulation of the surface is required, several sen-
sors can be linked together in a specific pattern
(see connection diagram below). The sensor cable
must not be laid alongside a power cable.
Air temperature regulation
TR 26 is also used with LK Room Temperature
Sensor FS 103, which should be fitted away from
sunlight or other heat sources. If overall tempera-
ture regulation is required, several sensors can be
linked together in a specific pattern (see connec-
tion diagram below). The sensor cable must not
be laid alongside a power cable.
1. LK Electronic Thermostat TR 26
a. Temperature setting 0 - 60 °C
b. Mode Indication.
c. ”Heating on” indicator
d. ∆t adjuster – range 0.5 to 5K.
2. LK Floor Sensor FK133/4 (4M lg.)
3. LK Room Temperature Sensor FS 103
4. LK Thermostat Housing with DIN rails;
space for two thermostats.
NOTE:
The items must be ordered using separate item numbers
(see technical data).
LK Electronic Thermostat TR 26
EN.33.C.35.1512
Assembly instructions | LK Electronic Thermostat TR 26
