EPH Controls RDT Operating instructions

Installation and Operation Guide
Recessed Room Thermostat
RDT

2
Factory Default Settings
3
Specications
4
LCD Display
5
Buttons
6
Wiring
7
Mounting & Installation
12
Locking the Keypad / Backlight
13
Menu Function
20
24
11
On / O Function & Adjusting the Target Temperature
15
22
Table of contents
17
23
21
25
14
Installation Instructions
Operating Instructions
Delay Start Control (On/O)
P0 1 Operating Mode
Nor (Normal Mode)
Time Proportional Integral Mode (TPI)
P0 2 Setting High and Low Limits
P0 3 Hysteresis HOn and HOFF
P0 4 Calibrate
P0 5 Setback Mode
FP Frost Protection
Resetting the Thermostat

Mains operated non-programmable
Room Thermostat with Setback
Installation Instructions

2RDT
Factory Default Settings
High and Low Temp. limitation: O
Keypad lock: O
Operating mode: Normal
Temperature indicator: ˚C
Frost protection: On (5˚C)
Setback temperature: 0˚C
HYS On: 0.4˚C
HYS OFF: 0.0˚C

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EPH Controls Ltd.
Specications
Contacts: Volt Free
Power supply / Input: 230VAC
Power consumption: <1W
Temperature range: 5…35˚C
Ambient temperature: 0…45˚C
Ambient admissible humidity: 5-95%RH
Contact rating: 10(3)A 230VAC
Dimensions: 95 x 95 x 40mm
Internal temperature sensor: NTC 100K
Backlight: White
IP rating: IP20
Pollution degree: 2
Hysteresis (Switching dierential): Adjustable from 0 to 1°C
0.1°C increments
Automatic action: 1C
Setback temperature: Adjustable 0 to 10˚C

4RDT
[1]
[10] [9] [8]
[11]
[3] [4] [5][2]
[6]
[7]
[12]
[1] Displays when setting target temperature.
[2] Displays current room temperature.
[3] Displays current / target temperature.
[4] Displays when changing mode setting.
[5] Displays when setting TPI mode.
[6] Displays when keypad is locked.
[7] Displays when the thermostat is calling for heat.
[8] Displays when thermostat is in the OFF mode.
[9] Displays when setting HIGH and LOW temperature limit.
[10] Displays during calibration mode.
LCD Display
[11] Displays when setting
hysteresis.
[12] Displays when
setback mode is
enabled.

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EPH Controls Ltd.
Buttons
OK Button
Down Button Up Button
Standby Button

6RDT
Wiring
Terminal Connections
LLive In
NNeutral In
Terminal 1 OFF - N/C Normally closed connection
Terminal 2 ON - N/O Normally open connection
Terminal 3 COM - Common connection
Terminal 4 SB - Setback connection
230V on Terminal 4: Thermostat works in Normal mode
0V on Terminal 4: Thermostat works in Setback mode
* If mains output is required terminals L and 3 must be electrically linked.

7
EPH Controls Ltd.
Mounting & Installation
Caution!
Installation and connection should only be carried out by a qualied person.
Only qualied electricians or authorised service sta are permitted to open the
thermostat.
If the thermostat is used in a way not specied 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 rst disconnected from
the mains.
This thermostat can be mounted to a recessed conduit box.

8RDT
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 oor level.
- Prevent direct exposure to sunlight or other heating /
cooling sources.
3) Use the fastening clip on the base of the thermostat to release
the front housing from the rear wiring box as per diagram on
page 9.
4) Wire the thermostat according to the wiring diagram on page 6.
5) Screw the rear wiring box to the recessed back box.
6) Attach the front housing to the rear wiring box until it clips
securely into place.
Mounting & Installation Continued

9
EPH Controls Ltd.
95
95
40.2
15.2
45 113

Operating Instructions
Mains operated non-programmable
Room Thermostat with Setback

11
EPH Controls Ltd.
Operating Instructions
Press to turn the thermostat On or O.
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’.
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.
On / O Function
Adjusting the Target Temperature

12 RDT
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.
There are three settings for selection.
‘AUt’ The backlight is on for 10 seconds when any button is pressed.
‘On’ The backlight is permanently on.
‘OFF’ The backlight is permanently o.
Use and to change the mode between AUTO, ON and OFF.
Press to conrm selection and to return to normal operation.
Backlight AUTO
To adjust the backlight setting, press and hold for 10 seconds.
‘AUt’ appears on the screen.

13
EPH Controls Ltd.
Backlight
Menu Function
This menu allows the user to adjust additional functions.
To access the menu, press and hold & together for 5 seconds.
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.
‘PO1’ will appear on the screen.
Press to select.
Use and to select between:
nOr (Normal mode)
dS (delay start mode)
tPi (Time proportional integral mode)
Press to conrm the mode.
P01 Operating Mode (Normal / Delay Start / TPI)

14 RDT
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.
P01 Operating Mode continued
22˚C
21˚C
20˚C
19˚C
18˚C
17˚C
Temp
Time Minutes
Graph (14.1): On / O Control
Target Temperature
200 40 60 80 100

15
EPH Controls Ltd.
Delay Start Control (On/O)
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 ash 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.
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.
48
42
36
30
24
18
12
6
0
0123456
Temperature below thermostat setting °C
Time delay after Delay Start activated in minutes
Graph (15.1): Delay Start Control

16 RDT
P01 Operating Mode continued
Delay Start Control (On/O) Continued
Delay start can be reactivated by:
1. Press to lower the target below the current temperature.
2. Press to conrm.
3. Press to increase the target temperature above the zone
temperature within 6°C .
4. Press to conrm.
The heating will be delayed as per the graph on page 15.
If the dierence between the actual temperature and the target is 1°C
the thermostat will delay starting for circa 40 minutes.
If the dierence between the actual temperature and the target is 3°C
the thermostat will delay starting for circa 24 minutes.
If the dierence 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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EPH Controls Ltd.
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 Bandwith section, TPI will
start to aect the thermostats operation. The thermostat will turn
on and o 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 aect the thermostats operation
1. The number of heating cycles per hour
2. The Proportional Bandwith
CyC – Number of Heating Cycles per hour 6 Cycles
This value will decide how often the thermostat will cycle the
heating on and o when trying to achieve the target temperature.
You can select 2/3/6 or 12.
P01 Operating Mode continued

18 RDT
22˚C
21˚C
20˚C
19˚C
18˚C
17˚C
Temp
Time Minutes
Heating On Heating O
Target Temperature
Proportional Bandwidth
200 40 60 80 100
Graph (18.1): TPI Control
Time Proportional Integral Mode (TPI) Continued
Pb -Proportional Bandwith 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.
P01 Operating Mode continued