Carel heaterSteam - Function Settings: Maintenance and Preheat; Cylinder Hours, Autotest, and Preheat

34
ENG
“heaterSteam” +0300080EN - rel. 1.0 - 27.04.2016
7.2.7 Cylinder operating hours (Service menu)
The “Cylinder op. hours” screen displays the eff ective number of cylinder
working hours.
Index Description Parameter
Ea07
Cylinder op.
hours
Display cylinder operating hours, reset hour counter
and set maintenance pre-alert threshold
Default: Pre-alert = 48 hours
Possible settings: 0-999
If the cylinder needs to be replaced, the hour counter must be reset using
the “Reset” parameter; the hour counter will then start again from zero.
The “Pre-alert” item sets the maintenance pre-alert, which is activated “x”
hours before the maintenance alarm, and where “x” is the value set for the
“Pre-alert” parameter. This allows time to plan the maintenance operation.
The “maintenance alarm” time is the number of cylinder operating hours
before it needs to be cleaned. During the start-up wizard, the feedwater
hardness is entered, and the ”maintenance alarm” depends on this value,
as shown in the table below:
Water hardness Maintenance alarm
0-10°f STOP for cleaning/maintenance 3000 hours
10-20°f STOP for cleaning/maintenance 1500 hours
20-30°f STOP for cleaning/maintenance 1000 hours
30-40°f STOP for cleaning/maintenance 800 hours
If during the wizard the value is set to “automatic”, rather than entering
the hardness value, the maintenance alarm is automatically associated
to the feedwater conductivity read by the conductivity meter. The
following table shows the dependency of the maintenance alarm on
water conductivity:
Water conductivity Maintenance alarm
1 - 50 μS/cm Warning at 3000 hours without STOP for cleaning
maintenance (it is assumed that the water comes from a
reverse osmosis system)
50 - 100 μS/cm STOP for cleaning/maintenance 3000 hours
> 100 μS STOP for cleaning/maintenance 1500 hours
The conductivity is read periodically, and the maintenance alarm times is
thus updated as a consequence.
Therefore, for example, if the water hardness is set to 15°f, the
“maintenance alarm” time will be 1500 eff ective cylinder operating
hours; if the “maintenance pre-alert” time is set to 48 hours (default), the
maintenance pre-alert will be signalled after 1452 hours.
7.2.8 Unit operating hours (Service menu)
To display information on unit operating hours, access the “Unit operating
hours” menu.
Index Description Parameter
Ea08
Unit operating
hours
Display unit operating hours
7.3 Menu E. Settings - b. Functions
7.3.1 Autotest (Installer menu)
To enable the autotest procedure when the unit is next started, access
the corresponding menu item.
Index Description Parameter
Eb01
En. Autotest Enable the autotest procedure.
Default: Enabled
This procedure checks operation of the level sensor; for further details see
chapter 6. “Start-up and user interface”.
7.3.2 Preheat cylinder water (Installer menu)
To ensure production starts quickly, the preheat function can be enabled.
In this way, even when there is no steam request, the water temperature
in the cylinder is kept at a value specifi ed by the user. When production
is next needed, the water is thus warmer than ambient temperature and
consequently production will start faster.
Index Description Parameter
Eb02
Preheating Enable preheat
Set the water temperature to maintain
Set water temperature off set
Defaults:
Preheat disabled
Water temp. set point in the cylinder = 80°C (176°F)
Off set = 3%rH (3°C / 5.4 °F)
Set point range: 50-80°C (122-194°F)
Off set range: 2-20%rH (0-20°C / 32-68°F)
The water temperature in the cylinder is read by the passive NTC
temperature probe in contact with the cylinder. The operating principle
of the preheat function is described in the following graphs, the fi rst for
control with probes, the second for control by external signal.
Preheat with autonomous modulating control with probes
The preheating function, if active, overlaps the control diagram and
modulates the power delivered to the heaters in relation to the water
temperature and the preheating set point. The operating principle of the
preheat function is described in the following graph:
P
OFF
ON
%rH
hy
max
Steam_Pr
P
min
BP
Oset
OFF
OFF
ON
hy
%rH
St
Vapore
Pre-riscaldo
Fig. 7.b
Key
Steam_pr Steam production %rH Humidity measurement
P
max
Max production hy Activation hysteresis
P
min
Min production BP Proportional band
St Set point