EPH Controls CRT2 Operation guide

CRT2
Room Thermostat
Installation and Operation Guide
Table of contents
Installation Instructions
Factory Default Settings
Specifications
LCD Display
Buttons
Wiring
Mounting & installation
Replacing the batteries
2
3
4
5
6
7
10
Operating Instructions
On / Off Function & Adjusting the Target Temperature
Locking the Keypad / Backlight
Menu
HYS Hysteresis HOn and HOFF
Calibrate
Setting High and Low limits
Operating Mode
Normal Mode (Nor)
Delay Start Control (On/Off )
Time Proportional Integral Mode (TPI)
Resetting the Thermostat
12
13
14
16
17
18
19
20
22
25
Battery operated non-programmable Room Thermostat
Installation Instructions
Factory Default Settings
High and Low Temp. limitation:
Keypad lock:
Operating mode:
Temperature indicator:
HYS On:
HYS OFF:
2
CRT2
Off
Off
Normal
˚C
0.4˚C
0.0˚C
Specifications
Contacts:
Power supply / Input:
Power consumption:
Volt Free
2 x AA Alkaline Batteries
Operating 30mW
Standby
<0.5mW
Temperature range:
5 … 35˚C
Ambient temperature:
0 … 45˚C
Ambient admissible humidity: 5-95%RH
Contact rating:
8(3)A, 230Vac
Switch output:
SPDT Volt Free
Dimensions:
91 x 91 x 26mm
Internal temperature sensor: NTC 100K
Backlight:
White
IP rating:
IP20
Pollution degree:
2
Hysteresis (Switching differential): Adjustable from 0 to 1°C
Automatic action:
0.1°C increments
1C
EPH Controls Ltd.
3
LCD Display
[1]
[2]
[3]
[4]
[5]
[6]
[7]
[8]
[9]
[10]
[11]
[12]
Displays when setting target temperature.
Displays current room temperature.
Displays current / target temperature.
Displays when changing mode setting.
Displays when setting in TPI mode.
Displays when the batteries need to be replaced.
Displays when the thermostat is calling for heat.
Displays when keypad is locked.
Displays when thermostat is in the OFF mode.
Displays when setting HIGH and LOW temperature limit.
Displays during
[2]
[5]
[6]
[3] [4]
calibration mode.
Displays when
[1]
set room temp mode cyc p band
setting hysteresis.
[7]
HYS calibrate high low limit off
[12]
4
CRT2
[11]
[10]
[9]
[8]
Buttons
Reset Button
OK Button
Standby Button
Down Button
Up Button
EPH Controls Ltd.
5
Wiring
3
2
1
ON COM OFF
Terminal Connections
6
Terminal 1
OFF - N/C Normally closed connection
Terminal 2
COM - Common connection
Terminal 3
ON - N/O Normally open connection
CRT2
Mounting & Installation
Caution!
ƒ Installation and connection should only be carried out by a qualified person.
ƒ Only qualified electricians or authorised service staff are permitted to open
the thermostat.
ƒ If the thermostat is used in a way not specified by the manufacturer, its
safety may be impaired.
ƒ Prior to setting the thermostat, it is necessary to complete all required
settings described in this section.
ƒ 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
3) To a surface mounting box
EPH Controls Ltd.
7
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 metres above the floor level.
- Prevent direct exposure to sunlight or other heating /
cooling sources.
3)
Use a philips screwdriver to loosen the screw on the
bottom of the thermostat to open the front housing.
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.
CRT2
90
90
26
45 113
9
Replacing the batteries
1)
10
is displayed when the batteries need to be replaced.
2)
Push in the battery compartment to release it.
3)
Replace the batteries with 2 x AA Alkaline batteries.
4)
Re-insert the battery compartment. Push it until it clicks into
place.
CRT2
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
room temperature.
When in the OFF mode the thermostat will display the current
room temperature and the word ‘OFF’.
Adjusting the Target Temperature
12
Press
to increase the target temperature from 5-35˚C.
Press
or wait 5 seconds. The target temperature is now saved.
Press
to decrease the target temperature from 5-35˚C.
Press
or wait 5 seconds. The target temperature is now saved.
CRT2
Locking the Keypad
To lock the thermostat, press and hold
and
for 10 seconds.
will appear on the screen. The buttons are now disabled.
To unlock the thermostat, press and hold
and
for 10
seconds.
will disappear from the screen. The buttons are now enabled.
Backlight
AUTO
There are two settings for selection.
‘AUt’
The backlight is on for 5 seconds when any button is
pressed.
‘OFF’
The backlight is permanently off.
To adjust the backlight setting, press and hold
for 10 seconds.
‘AUt’ appears on the screen.
Use
Press
and
to change the mode between AUTO and OFF.
to confirm selection and to return to normal operation.
EPH Controls Ltd.
13
Menu
This menu allows the user to adjust additional functions.
To access the menu, press and hold
and
together for 5 seconds.
HYS – Hysteresis HOn and HOf
HOn 0.4°C HOff 0°C
This menu allows the installer to change the switching differential of
the thermostat when the temperature is rising and falling.
If ‘HYS ON’ is set at 0.4˚C and the setpoint is 20˚C, then the thermostat
will switch on when the temperature drops below 19.6˚C.
If ‘HYS OFF’ is set at 0.2˚C and the setpoint is 20˚C, then the thermostat
will switch off when the temperature reaches 20.2˚C.
To access this setting press and hold
and
together for 5
seconds.
‘HYS’ will appear on the screen. Press
to select.
‘HOn’ will appear on the screen.
14
Press
and temperature will begin to flash.
Use
and
to select the ‘HOn’ temperature, press
CRT2
to confirm.
‘HOF’ appears on the screen.
Press
and the temperature will begin to flash.
Use
and
Press
to return to normal operation.
to select the ‘HOF’ temperature, press
EPH Controls Ltd.
to confirm.
15
Calibrate
This menu allows the installer to calibrate the temperature of the
thermostat.
To access this setting press and hold
and
seconds.
‘HYS’ will appear on the screen.
Press
until ‘CALIBRATE’ flashes on the screen.
Press
to select.
The actual temperature will flash on the screen.
16
Press
and
Press
to confirm the temperature.
Press
to return to normal operation.
to calibrate the temperature.
CRT2
together for 5
Setting High and 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
seconds.
and
together for 5
‘HYS’ will appear on the screen.
Press
until ‘LIMIT’ flashes on the screen.
Press
to select.
‘HIGH LIMIT’ will appear on the screen, the temperature will
begin to flash.
Use
and
Press
to confirm.
to select the high limit for the thermostat.
‘LOW LIMIT’ will appear on the screen, the temperature will begin
to flash.
Use
and
Press
to confirm.
Press
to return to normal operation.
to select the low limit for the thermostat.
‘LIMIT’ will appear on the screen.
EPH Controls Ltd.
17
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
and
together for 5 seconds.
‘HYS’ will appear on the screen.
Press
until ‘MODE’ appears on the screen.
Press
to select.
Use
and
to select between:
nOr (Normal mode)
dS (delay start mode)
tPi (Time proportional integral mode)
Press
18
to confirm the mode.
CRT2
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 (19.1): On / Off Control
Temp
22˚C
Target Temperature
21˚C
20˚C
19˚C
18˚C
17˚C
0
20
40
60
80
EPH Controls Ltd.
100
Time Minutes
19
Operating Mode (Normal
/ Delay Start / TPI) continued
Delay Start Control (On/Off)
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 (20.1): Delay Start Control
20
48
E.g: If the temperature is 6˚C
below the thermostat target,
the thermostat will call for
heat immediately.
42
36
30
24
18
12
6
0
0
4
2
5
1
3
6
Temperature below thermostat setting °C
CRT2
If the temperature is 2˚C
below the target, the
thermostat will not call for
heat for 32 minutes.
Delay Start Control (On/Off) Continued
Delay start can be reactivated by:
1.
Press
to lower the target below the current temperature.
2.
Press
to confirm.
3. Press
to increase the target temperature above the zone
temperature within 6°C .
4.
Press
to confirm.
The heating will be delayed as per the graph on page 20.
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.
EPH Controls Ltd.
21
Operating Mode (Normal
/ Delay Start / TPI) continued
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.
22
CRT2
Time Proportional Integral Mode (TPI) Continued
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 (23.1): 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
EPH Controls Ltd.
23
Operating Mode (Normal
/ Delay Start / TPI) continued
Time Proportional Integral Mode (TPI) Continued
Once TPI mode is selected, ‘CYC’ and ‘06’ will appear on the screen.
Use
and
Press
to confirm.
to select from 2,3,6 or 12.
‘P Band’ and ‘2.0’ will appear on the screen.
24
Use
and
Press
to confirm.
Press
to return to normal operation.
to select from 1.5 to 3.0.
CRT2
Resetting the Thermostat
To reset the thermostat to factory settings, locate the
button on the left hand side of the thermostat.
Press the
reset
reset button and release it.
‘nO’ will flash on the screen.
Press
.
‘YES’ will flash on the screen.
Press
to confirm.
The thermostat will restart and revert to its factory settings.
EPH Controls Ltd.
25
EPH Controls IE
[email protected]
www.ephcontrols.com/contact-us
+353 21 471 8440
Cork, T12 F753
EPH Controls UK
2026-01-29_CRT2_DS_PK
© 2026 EPH Controls Ltd.
[email protected]
www.ephcontrols.co.uk/contact-us
+44 1933 322 072
Harrow, HA1 1BD
">