Installation of PT21:
Install the thermostat on a suitable place, where its operation would not be influenced by
direct flow of hot air from the heater, by solar radiation and other disturbing influences. Also
avoid the installation on outer wall.
PT21 thermostat consists of two parts: the front one - the microprocessor one (Pic.1) and
rear one - the switching one. In this way very easy and quick installation of the
thermostat into installation box of KU/KP68 type is achieved and very comfortable
programming directly from your armchair.
Procedure:
1. Open the case of PT21 in the place indicated by arrow on Pic.1 and so divide the thermostat to two parts.
2. Grasp the rear (switching) part and fasten it into installation box (see Pic.2) at the height of minimally 1.5 m.
3. Unscrew the screw as indicated by arrow (Pic.2) and lift of the cover. Under this cover, there is the relay
and terminal strip, to which the cables from boiler should be connected (Pic.2).
4. Grasp the front part of PT21, slide of the cover (Pic.1a), insert two pencil alkali batteries 2x 1.5 V and
program the thermostat according to operating instructions.
5. Afterwards, snap the front part from above to the lower part of PT21 and the thermostat is ready for
operation. (We recommend to use " Tes t " button for testing)
The installation of PT21 may be performed only by a person with appropriate
qualification in electrical engineering.
ROOM THERMOSTAT PT21
PT21 is a digital room thermostat for automatic regulation of heating,
offering the possibility to set 6 different temperatures (5 to 40°C) for
each day (minimal duration of time interval to be set is 10 minutes).
Further advantages:
- different temperature program for each day
- setting the HYSTERESIS in the range from 0.1°C to 1.5°C
- simple control and programming
- possibility to make a short-term change in program temperature
- easy installation to all types of installation boxes KU/KP68
- economic mode "holiday" for maximally 99 days ( )
- low power consumption
- copying of days by a single button (Kopi)
- information on operating hours of the boiler (Suma)
- temperature regulation at steps of 0.5°C
- multifunctional display
- retention of memory contents, when the batteries are replaced
sooner than after approx. 25s
Specification PT21:
Power supply alkali batteries 2 x 1,5 V typ AA/R6
Number of adjustable temp. for each day 6 different temperatures
Hysteresis 0,1; 0,2; 0,3; 0,4; 0,5; 1,0; 1,5°C
Minimal programming time 10 minutes
Range of possible temp. 5 to 40°C
Step of temperature setting 0,5°C
Minimal step of indication 0,1°C
Measurement accuracy 0,5°C
Output relay, max. 5A/250V AC
