Operating Instructions
Page 2 of 3
CDT2 Room Thermostat
with Delay Start
20221103_CDT2-230-DS-TPI_Opsins_PK
EPH Controls Ireland
[email protected] www.ephcontrols.com
EPH Controls UK
[email protected] www.ephcontrols.co.uk
11. Adjusting the switching differential (Normal)
12. Adjusting the setpoint temperature
Press the button once, Diff set will appear on the screen.
The factory default switching differential of 0.40C will appear on the screen.
Press the and buttons to select the desired differential from 0.2 - 1˚C.
Press the button to return to normal operation.
Set
Press the or buttons to adjust the temperature setpoint.
13. Changing the thermostat mode
14. Normal control mode (On/Off )
15. Delay start control mode
P
1
- Normal On/Off mode
P
2
- Delay Start mode (DS)
P
3
- Time Proportional Integral Mode (TPI)
Press the ‘
Reset’
button at the side of the thermostat.
P
1
will appear on the screen.
Use the or buttons to change between P
1
to P
2
and P
3.
Select P
1
for normal operation.
Select P
2
for delay start.
Select P
3
for TPI – If P3 is selected you can press the button to choose
the amount of cycles and then press the button to choose the
proportional bandwidth.
Press the
‘standby’
button to confirm.
See section 16 for more information on TPI.
When the temperature falls below the setpoint temperature, the flame
symbol will appear and the thermostat will switch on.
When the temperature rises above the setpoint temperature, the flame
symbol will disappear and the thermostat will switch off.
22˚C
21˚C
20˚C
19˚C
18˚C
17˚C
Temp
Time Minutes
Graph (14.1): On / Off Control
Setpoint Temperature
20
0
40
60
80
100
Delay start is an energy saving mode.
When the delay start function is active the flame symbol will continuously
flash on the screen. When in this mode the activation of the thermostat is
delayed by a variable time depending on the current temperature, setpoint
temperature and also the fall in temperature from when the delay start has
activated. See graph (15.1) Delay Start Control.
The flame symbol will continue to flash until the thermostat activates.
When activated the thermostat will allow the heating system time to reach
the setpoint and delay start will remain inactive until it reaches this setpoint.
Delay start can be reactivated by:
Lowering the setpoint below the current temperature, pressing the
‘standby’
button to set the temperature, then raising the setpoint above the
zone temperature within 6˚C of the setpoint.
The heating will be delayed as per the line on the graph.
If the difference between the actual temperature and the setpoint is 10C the
thermostat will delay starting for circa 40 minutes.
If the difference between the actual temperature and the setpoint is 30C the
thermostat will delay starting for circa 24 minutes.
If the difference is 60C or more, the heating will be switched on immediately.
The time delay will change if the temperature drops from the original
calculation.
To deactivate Delay Start, see section 13.
10. High and Low temperature limitation
OFF
Set
An upper and lower temperature limit may be chosen.
Press and hold the and buttons for 10 seconds.
“Limit OFF” will appear on the screen.
Press the button to select “Limit ON” mode.
Press the button to confirm you wish to adjust the high limit temperature.
Press the and buttons to select the high limit temperature.
Press the button to select the low limit temperature mode.
Press the and buttons to select the low limit temperature.
Press the button and the thermostat is ready for operation.
“Limit” will appear on the screen.
To deactivate High and Low temperature limitation.
Press and hold the and buttons for 10 seconds.
“Limit ON” will appear on the screen.
Press the button to deactivate this function.
“Limit OFF” will appear on the screen.
Press the button and the thermostat is ready for operation.
Set
Set
Set
Set
Set
48.0
42.0
36.0
30.0
24.0
18.0
12.0
6.0
0.0
0
1
2
3
4
5
6
Temperature below thermostat setting °C
Time dela
y af
ter D
ela
y S
tar
t ac
tiv
at
ed in minut
es
Graph (15.1): Delay Start Control
