background image

ROOM THERMOSTAT

PT21

COMFORT PROGRAMMING DIRECTLY 

IN YOUR CHAIR

-

FOR ALL TYPES OF HEATING 

AND AIR-CONDITIONING 
SYSTEMS

- ENERGY SAVING UP TO 30% 

MADE IN CZECH REPUBLIC

Indication 
of day

Real or 
set time

Switching on
of the boiler

Program 
number

Time setting

Manual operation

Indication of 
HOLIDAY mode

Indication 
of low battery 

Seconds or 
temperature

Mode indication
- P required temp.
- H sum
- C Copy
- O Off

Display description:

Description of elements:

Next step, information 
on required temperature

Function switch

Switching off 
of the boiler, 
reset 
of boiler 
operating 
hours 

Boiler testing

Setting hysteresis

Sum of boiler 
operating hours

Copying
of programs

Holiday function

Change of the day

Setting the time 
in program

Regulation of temperature, 
or +/- minutes, setting 
of current time, 
reset of seconds

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 " 

Test

" 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

CERTIFICATE OF GUARANTEE

(guarantee period for the product amounts to 2 years)

product No.:

date of sale:

stamp of shop:

examined by:

MADE IN CZECH REPUBLIC

ELEKTROBOCK CZ s.r.o.

Blanenská 1763
Kuřim 664 34 

Tel./fax: +420 541 230 216

http:// www.elbock.cz

Send the thermostat for guarantee and after-guarantee service

to manufacturer's address. 

Table for registration of your programs

1

2

3

4

5

6

Mon

Tue

Wed

Thu

Fri

Sat

Sun

day

progr.

T

e

mper

atur

e and

time set

Pic.1

Pic.1a

PT21

BOILER

battery compartment

use only alkali battery

2x1.5 V type AA/R6

Pic.2

ON

Terminals 1 and 2
are interconnected
when the thermostat 
is switched on 

Terminals 2 and 3
are interconnected 
when the thermostat 
is not switched on  

openings for mounting screws

  

Boiler connection

  

pt21_en.qxd  23.6.2006  16:39  Page 1

Reviews: