Unical ALKON R 18, Installation And Servicing Manual

42

Inspections and servicing schedule

Relationship between the temperature (°C) and the nominal
resistance (Ohm) of the CH sensor and the DHW sensors.

T°C

0

1

2

3

4

5

6

7

8

9

0

32755

31137

29607

28161

26795

25502

24278

23121

22025

20987

10

20003

19072

18189

17351

16557

15803

15088

14410

13765

13153

20

12571

12019

11493

10994

10519

10067

9636

9227

8837

8466

30

8112

7775

7454

7147

6855

6577

6311

6057

5815

5584

40

5363

5152

4951

4758

4574

4398

4230

4069

3915

3768

50

3627

3491

3362

3238

3119

3006

2897

2792

2692

2596

60

2504

2415

2330

2249

2171

2096

2023

1954

1888

1824

70

1762

1703

1646

1592

1539

1488

1440

1393

1348

1304

80

1263

1222

1183

1146

1110

1075

1042

1010

979

949

90

920

892

865

839

814

790

766

744

722

701

TABLE OF RESISTANCE VALUES AS A FUNCTION OF THE HEATING SENSOR (SR) AND DHW (SS) TEMPERATURE SENSORS

Example: At 25°C, the nominal resistance is 10067 Ohm

At 90°C, the nominal resistance is 920 Ohm

To ensure the continued safe and efficient
operation of the boiler it is highly
recommended that it is checked at regular
intervals and serviced when necessary, and
that only original spare parts are used.

Regular attention will prolong the life of the
boiler.

If the boiler is not checked and serviced
regularly it could cause material and personal
damages.

For this reason UNICAL recommends that a servicing contract
should be made with our authorized After Sales Service
Assistance Centre.

The boiler must have regular maintenance and cleaning in
order to ensure reliable and efficient operation.  Regular
attention will prolong the life of the boiler.

The frequency of servicing  will be determined by the service
engineer and will depend on the appliance’s state of condition.

These adjustments can be performed only by Service Centres
authorized by UNICAL.
UNICAL is not responsible for any damages caused to
persons, animals and goods deriving from this infringement.

For a better operation of your appliance follow the suggested
servicing as shown on page 43

4

INSPECTION AND SERVICING SCHEDULE

INSTRUCTIONS FOR INSPECTION AND
SERVICING

To ensure a long life to all your boiler
components and in order not to alter the
conditions of the approved product, only
original UNICAL spare parts must be used.

Before servicing always carry out the following steps:
-

Disconnect the mains electricity supply.

-

Separate the appliance from the electrical supply by me-
ans of a separating device with an opening contact of at
least 3 mm (for example safety devices or power switches)
and ensure yourself that it cannot be accidentally reinser-
ted.

-

Close the on-off valve fitted upstream of the boiler.

-

If necessary, and in function of the type of work to be car-
ried out, close any on-off valves fitted on the CH flow and
return pipes, as well as the cold water inlet valve.

-

Remove the appliance’s front panel.

After having carried out all the necessary maintenance  work
always follow these steps:
-

Open the CH flow and return valves as well as the cold
inlet valve (if previously closed),

-

Purge and, if necessary, proceed with restoring the hea-
ting system’s pressure until a pressure of 0,8/1 bar is rea-
ched.

-

Open the on-off gas cock.

-

Reconnect the appliance to the electrical supply and switch
on the mains electrical supply.

-

Test for gas soundness, on the gas side and on the water
side.

-

Replace the appliance’s front panel.