HRT
Room Thermostat
Installation and Operation Guide
Table of contents
Installation Instructions
Factory default settings
Specifications
LCD Display
Buttons
2
3
4
5
Wiring
Mounting & installation
Replacing the batteries
6
7
10
Operating Instructions
On / Off Function & Adjusting the target temperature
Locking the Keypad / Backlight
Menu Function
P0 1 Operating Mode
Nor (Normal Mode)
Delay Start Control (On/Off )
Time Proportional Integral Mode (TPI)
P0 2 Setting High and Low limits
P0 3 Hysteresis HOn and HOff
P0 4 Calibration
P0 5 Frost Protection
P0 7 Resetting the Thermostat
12
13
14
15
16
18
20
21
22
23
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Battery operated non-programmable Room Thermostat
Installation Instructions
Factory default settings
2
Contacts:
Volt Free
High and Low Temp. Limitation:
Off
Keypad lock:
Off
Backlight:
Auto
Operating mode:
Normal
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Specifications
Power supply / Input:
Power consumption:
2 x AA Alkaline Batteries
Operating <0.05W
Standby <0.2mW
Temperature range:
Ambient temperature:
Ambient admissible humidity:
Contact rating:
Switch output:
Dimensions:
Temperature sensor:
Backlight:
IP rating:
Pollution degree:
Switching differential:
5 … 35˚C
0 … 45˚C
5-95%RH
8(3)A, 230Vac
SPDT Volt Free
85 x 85 x 36mm
NTC 100K
White
IP20
2
Adjustable from 0.0 – 1.0°C
0.1°C increments
1C
Automatic action:
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LCD Display
[1]
Shows the current / target temperature.
[2]
Displayed when batteries need to be replaced.
[3]
If the keypad is locked, the lock symbol is
displayed.
[4]
When the thermostat is calling for heat, the
flame symbol is displayed.
[5]
When a high or low temperature limit is set,
‘LIM’ is displayed.
[6]
Displayed when delay start is enabled.
[1]
[2]
[3]
[6]
4
[5]
[4]
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Buttons
Reset
Handwheel
Button
Standby Button
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Wiring
1
2
3
OFF COM ON
Terminal Connections
1
6
OFF - N/C Normally closed connection
2
COM - Common connection
3
ON
- N/O Normally open connection
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Mounting & Installation
Caution!
Installation and connection should only be carried out by a qualified
person.
Only qualified electricians or authorised service staff are permitted to
open the thermostat.
If the thermostat is used in a way not specified by the manufacturer,
its safety may be impaired.
Prior to setting the thermostat, it is necessary to complete all required
settings described in this section.
Before commencing installation, the thermostat must be first
disconnected from the mains.
This thermostat can be mounted in the following ways:
1) Directly mounted on wall
2) To a recessed conduit box
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Mounting & Installation Continued
8
1)
Remove the thermostat from its packaging.
2)
Choose a mounting location so that the thermostat can
measure the room temperature as accurately as possible.
- Mount the thermostat 1.5 meters above the floor level.
- Prevent direct exposure to sunlight or other heating
/ cooling sources.
3)
To open the front housing
a) use a philips screwdriver to loosen the screw
on the bottom right of the thermostat.
b) insert and rotate a 3.5mm flat screwdriver into
the slot on the bottom left.
4)
Wire the thermostat according to the wiring diagram
on page 6.
5)
Screw the backplate onto a back box or directly to the
surface.
6)
Close the front housing and tighten the screw on the
bottom of the thermostat.
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26
85
85
45 113
b)
a)
Replacing the batteries
1)
is displayed when the batteries need to be
replaced.
2)
Push in the battery compartment on the bottom of
the thermostat to release it.
10
3)
Replace the batteries with 2 x AA Alkaline batteries.
4)
Re-insert the battery compartment. Push it until it
clicks into place.
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Battery operated non-programmable Room Thermostat
Operating Instructions
On / Off Function
Press
to turn the thermostat On or Off.
When in the ON mode the thermostat will display the current
ambient temperature.
When in the OFF mode the thermostat will display the current
ambient temperature and the word ‘OFF’.
Adjusting the target temperature
Rotate
clockwise to increase the target temperature.
Press
saved.
or wait 5 seconds. The target temperature is now
Rotate
anti-clockwise to decrease the target temperature.
Press
saved.
or wait 5 seconds. The target temperature is now
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Locking the Keypad
To lock the thermostat, press
for 10 seconds.
will appear on the screen. The buttons are now disabled.
To unlock the thermostat, press
for 10 seconds.
will disappear from the screen. The buttons are now
enabled.
Backlight
AUTO
There are three settings for selection.
‘bL AUtO’ The backlight is on for 5 seconds when any button
is pressed.
‘bL OFF’ The backlight is permanently off.
To adjust the backlight setting, press
for 10 seconds.
‘bL AUtO’ appears on the screen.
Rotate
to change the mode between AUTO and OFF.
to confirm selection and to return to normal
Press
operation.
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Menu Function
This menu allows the user to adjust additional functions.
P0 1 – Operating Mode
(Normal
/ Delay Start / TPI)
There are three settings for selection, Normal, Delay Start or TPI
mode. The default setting is Normal.
Press and hold the
and
together for 5 seconds,
‘P01 & Nor’ will appear on the screen,
Press
to select.
Rotate
to select between
Nor (Normal mode)
dS (delay start mode)
tPi (Time proportional integral mode)
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Press
to confirm the mode.
Press
to return to normal operation.
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P0 1 – Operating Mode (Normal
/ Delay Start / TPI)
Nor (Normal Mode)
When the temperature falls below the target temperature,
will appear and the thermostat will activate the demand
for heat.
When the temperature rises above the target temperature,
will disappear, and the thermostat will cancel the
demand for heat.
Graph (15.1): On / Off Control
Temp
22˚C
Target Temperature
21˚C
20˚C
19˚C
18˚C
17˚C
0
20
40
60
80
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100
Time Minutes
15
P0 1 – Operating Mode (Normal
/ Delay Start / TPI)
Delay Start Control (On/Off)
When the delay start mode is active, ‘dS’ will appear
continuously on the screen. When in this mode the
thermostat is delayed by a variable time depending on the
current temperature, target temperature and also the fall in
temperature from when the delay start has activated. The will
flash until the thermostat activates.
When activated the thermostat will allow the heating system
time to reach the target and delay start will remain inactive until
it reaches this target.
Time delay after Delay Start activated in minutes
Graph (16.1): Delay Start Control
16
48
42
36
30
24
18
12
6
0
0
4
2
5
1
3
6
Temperature below thermostat setting °C
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E.g: If the temperature is 6˚C
below the thermostat target,
the thermostat will call for
heat immediately.
If the temperature is 2˚C
below the target, the
thermostat will not call for
heat for 32 minutes.
Delay start can be reactivated by:
1.
Lower the target below the current temperature.
2.
Press
3.
Increase the target above the zone temperature within 6°.
4.
Press
to set the temperature.
to confirm.
The heating will be delayed as per the graph on page 16.
If the difference between the actual temperature and the
target is 1°C the thermostat will delay starting for circa 40
minutes.
If the difference between the actual temperature and the
target is 3°C the thermostat will delay starting for circa 24
minutes.
If the difference is 6°C or more then the thermostat will be
switched on immediately.
The time delay will change if the temperature drops from the
original calculation.
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P0 1 – Operating Mode (Normal
/ Delay Start / TPI)
Time Proportional Integral Mode (TPI)
When the thermostat is in TPI mode and the temperature is
rising in the zone and falls into the Proportional Bandwidth
section, TPI will start to affect the thermostats operation. The
thermostat will turn on and off as it gains heat so that it doesn’t
overshoot the target by too much. It will also turn on if the
temperature is falling so it doesn’t undershoot the target which
will leave the user with a more comfortable level of heat.
There are 2 settings that will affect the thermostats operation.
1.
The number of heating cycles per hour
2.
The Proportional Bandwidth
CyC – Number of Heating Cycles per hour
6 Cycles
This value will decide how often the thermostat will cycle
the heating on and off when trying to achieve the target
temperature. You can select 2/3/6 or 12.
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Pb -Proportional Bandwidth
2°C
This value refers to the temperature below the target at which
the thermostat will start to operate in TPI control. You can set
this temperature from 1.5°C to 3.0°C in 0.1°C increments.
Graph (19.1): TPI Control
Temp
22˚C
21˚C
Target Temperature
20˚C
Proportional Bandwidth
19˚C
18˚C
17˚C
0
Heating On
20
40
60
80
100
Time Minutes
Heating Off
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P0 2 Setting High & Low limits
Hi 35°C Lo 5°C
This menu allows the installer to change the minimum and
maximum temperatures that the thermostat can be set at.
To access this setting press and hold
and
together for
5 seconds. ‘P01 & Nor’ will appear on the screen. Rotate
clockwise. ‘P02 & HI LO’ will appear on the screen. Press
to
select. ‘OFF’ & ‘LIM’ will appear on the screen. Rotate
to select
‘ON’ and press to confirm. ‘Hi LIM’ will appear on the screen and
the temperature will begin to flash. Rotate
to select the high
to confirm. ‘Lo LIM’ will appear
limit for the thermostat. Press
on the screen and the temperature will begin to flash. Rotate
to select the low limit for the thermostat. Press
to confirm.
The settings will be saved and the user will be returned to the
previous screen. Press
20
to return to normal operation.
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P0 3 Hysteresis HOn & HOff
HOn 0.4°C HOff 0.0°C
This menu allows the installer to change the switching differential
of the thermostat when the temperature is rising and falling.
To access this setting press and hold
and
together for
5 seconds. ‘P01 & Nor’ will appear on the screen. Rotate
clockwise until ‘P03 & HOn’ appears on the screen.
Press
to select. ‘HOn’ will remain on the screen and the
temperature will begin to flash. Use
temperature, press
to select the ‘HOn’
to confirm. ‘HOff’ appears on the screen
and the temperature will begin to flash.
Use
to select the ‘HOff’ temperature, press
to confirm.
The settings will be saved and the user will be returned to the
previous screen. Press
to return to normal operation.
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P0 4 – Calibration
This menu allows the installer to calibrate the temperature
of the thermostat.
To access this setting press and hold
and
together for 5
seconds.
‘P01 & Nor’ will appear on the screen.
Rotate
clockwise until ‘P04 & CAL’ appears on the screen.
Press
to select.
Current actual temperature will appear on the screen.
Rotate
clockwise or anti clockwise to calibrate the
temperature.
Press
to confirm the temperature.
The current temperature will be saved and the user will be
returned to the previous screen.
Press
22
to return to normal operation.
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P0 5 – Frost Protection
On
Frost protection is built into this thermostat, it is pre fixed to 5°C
and is not adjustable.
It will only be activated when the thermostat is in the standby
mode and the temperature drops below 5°C.
To access this setting, press and hold
and
together for
5 seconds.
‘P01 & Nor’ will appear on the screen.
Rotate
clockwise until ‘P05 & Fr’ appears on the screen.
Press
to confirm.
Rotate
to switch between ON and OFF.
Press
to confirm selection.
The setting will be saved and the user will be returned to the
previous screen.
Press
to return to normal operation.
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P0 7 – Resetting the Thermostat
This menu allows the user to reset the thermostat to factory
settings. To access this setting, press and hold
and
together for 5 seconds. ‘P01 & Nor’ will appear on the screen
Rotate
until ‘P07 & rst’ appears on the screen.
Press
to confirm. ‘rst’ will appear on the screen an ‘nO’
will flash. Rotate
clockwise. ‘rst’ will remain and ‘YES’ will
flash on the screen. Press
to confirm. The thermostat will
restart and revert to its factory defined settings.
Note:
If installer menu is inaccessible there is the option of a master
reset by using the button located on the left hand side of the
thermostat. Press this button and follow the instructions above.
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Notes
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[email protected]
www.ephcontrols.com/contact-us
+353 21 471 8440
Cork, T12 F753
2026-04-01_HRT_DS_82 x 82_PK
[email protected]
www.ephcontrols.co.uk/contact-us
+44 1933 322 072
Harrow, HA1 1BD
© 2026 EPH Controls Ltd.
EPH Controls UK
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