Strebel S-CB Px 120, Installation Operating & Maintenance Manual

Page: 78 / 118

S-CB Px 120 Manual 78
11.3.7. A
NTI
-L
EGIONNAIRES
’
DISEASE FUNCTION
(
PASTEURISATION
)
This function can only be used for an “indirect” programmed boiler (parameter P4 AA = 1), on which a DHW pro-
gram is active.
To prevent Legionnaires' disease the boiler (software) provides a function for heating up the hot water storage
tank (once a week) to a higher water temperature then the normal active hot water set point. Also the period, that
this “higher” water temperature function must be active, can be programmed.
NOTICE: The standard factory setting for this Legionnaires' disease (pasteurisation) function is “OFF”. To activate
this Legionnaires' disease function, some parameters must be programmed by the manufacturer/supplier. The
starting day and starting time of this Legionnaires' disease function can be programmed at the control panel of the
boiler.
There are several parameters being used for this function. Three of these parameters are shown in the following
graph.
With parameter P2 KI the heating (CH) demand can be interrupted to provide heat for the anti-Legionnaires’ dis-
ease demand. When no interruption is activated the boiler will wait for the end of the heat demand before the anti-
Legionnaires’ disease function starts. The standard factory setting for this function is “OFF”.
The settings of these parameters
P5 CI , P5 CJ and P5 CD must be programmed according to all applicable anti
Legionnaires’ disease preventing regulations.
The setting of these parameters can only be done by the manufacturer/supplier of the water heater or by a techni-
cian with access to programming level 2, at the control panel of the unit without the use of a computer.
NOTICE: The use and activation of this function won’t guarantee a Legionnaires’ disease free installa-
tion. The responsibility for a Legionnaires' disease free installation remains at the end-user/owner.
P5CI = 5°C
This is the bandwith within which the Legion-
naires' temperature must stay during the pro-
grammed period. In this example the temperature
is allowed to fluctuate between 65°C and 70°C
during the anti Legionnaires' function.
P5CJ = 80 min.
This is the duration within which the water
temperature must be between the 65°C
and 70°C.
P5CD = 70°C
This is the maximum temperature
during anti Legionnaires' disease
function period.
Normal setting
water temperature.
Start of the anti Legionnaires'
disease program (start day and
time can be programmed) .
Normal setting water
temperature.
Time (10 min steps)
Wa
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