OPER HOURS CH
OPER HOURS dHW
OUTSIdE TEMP
TEMP ANd POWER
4
C.H. OPERATING HOURS
FURTHER INFORMATION
Value of the boiler operating hours for central heating. The LCD value means 906
hours and 43 minutes (the maximum value is 9999 hours and 999 minutes).
Resetting hours:
After displaying the operating hours, turn the “ “ button
anti-clockwise.
HOT SERVICE WATER OPERATING HOURS
Value of the boiler operating hours for hot service water heating. The LCD value
means 906 hours and 43 minutes (the maximum value is 9999 hours and 999
minutes).
Resetting hours:
After displaying the operating hours, turn the “ “ button
anti-clockwise.
INFORMATION ON EXTERNAL TEMPERATURE
Information on the current external temperature provided
a sensor is connected to the boiler!
INFORMATION ON C.H. TEMP. AND MODULATION OUTPUT
Required C.H. = C.H. temperature calculated according to the equi-
therm curve selected, irrespective of the possible min. and max. tempera-
ture of C.H. water; the value in brackets is the required temperature with
respect to the min. and max. C.H. temperature set (see page 7).
Current C.H. = current central heating water temperature
Modul. power = modulation power of the boiler in %
ERROR MESSAGES
If the communication line between the thermostat and boiler is disconnected or interrupted,
the LCD displays the “LINE DISCONNECTED” message (at first connection, the thermostat
must be connected via the OT line to the boiler for about 30 minutes).
This system features a long time of clock operation backup – for more than 7 days!
The thermostat must be connected to the OT line for at least 2 days.
In case of a too long communication line failure, you must set the date and time, but the con-
stants and programs remain saved in the thermostat!
In this case, the “SET TIME” reminder appears on the last line of the display.
The OpenTherm protocol allows sending of error messages of different importance from the
boiler to the thermostat. PT52 shows these messages on the last line of the display:
- E xxx , where the xxx value may be 001 to 255. This type of errors may vary according to the boiler
manufacturer; therefore, you must contact a service technician or the manufacturer. The errors may
include, for example: wrong flue gas exhaust, external temperature sensor error, etc.
- Temp. measurement error = the internal sensor of the thermostat is faulty; contact the manufacturer.
- OPT error - central heating temperature = information on the current central heating temperature not
received from the boiler, contact the boiler service.
By successively pressing the “ “ button in the AUTO/MANU modes, you can view further information which
the boiler sends to the thermostat (attention: this information may differ according to the boiler type):
Additional information may be displayed: flow of water in liters, and temperature return!
