Slant/Fin VSL-160C Part C - Manual (Page 2)

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13.12 - Delays,
alarms and
protective actions
To protect the life of the appliance,
improve comfort, and maximize energy
savings, the following timings have
been incorporated into the control
logic:
a - Pump delay: each time the room
thermostat is satisfi ed, the circulator
pump continues to run for 1 minute;
b - DHW delay: each time the domestic
hot water demand is satisfi ed, a 2
minutes delay must pass before the
heating service is allowed to restart;
c - Protection against legionnaires
bacteria: if the boiler is connected
to a DHW storage tank the boiler
will increase the tank temperature
to 140 °F (60 °C) every seven days,
prevent the formation of legionnaires
bacteria. This function is displayed
by .
d - DHW alarm: if the call for domestic
hot water lasts for longer than two
hours, an 01 alarm is generated.
This function is only for boilers set
up to provide instantaneous DHW.
13.11 - Boiler
switch settings
The control board shown in Figure
3-1, item “14”, contains a series of
switches that allow the boiler to be
confi gured to match the application.
The table below lists each switch and
its corresponding funtions.
CAUTION!!!
This freeze
protection function is
conceived to protect the boiler
only, not the heating system.
CAUTION!!!
Because the
boiler’s freeze protection
function depends from the
electrical supply and from the
gas supply, it is mandatory
install a safety device that
alarm the user in a case
the boiler room will reach a
temperature near 35°F (2°C)
Once the boiler has reached a
temperature of 45 °F (7 °C), the
heating pump will automatically
comes on. If the temperature falls
below 35 °F (2 °C), the burner
will light to prevent the boiler from
freezing.
If the boiler will not be used for long
time it should be drained per Sections
14.10 and 14.11.
13 - USE
e - Time delay in restarting the burner:
in its normal functioning state, except
when providing domestic water,
every time the burner stops, there is
a delay time of 3 minutes before the
boiler restarts again.
13.13 - Circulator
pump and three way
valve protection
During the summer months, the
circulator is run once a day for around
15 seconds to prevent it from seizing.
At the same time, the three way valve
(if present) is activated for the same
reason.
13.14 - Boiler’s
Freeze protection
CAUTION!!!
For the freeze
protection function to work, the
boiler must remain connected
to the electrical and gas
supplies with knobs “7” and
“11” in Figure 13-1, in the OFF
position.
CAUTION!!!
Improper setting
of these switches could cause the
boiler to malfunction resulting in
improper system performance.
Only a qualifi ed technician, with an
in-depth knowledge of the boilers’
control system, should change
them.
SWITCH Position Description
1
OFF Boiler without production of D.H.W
ON Boiler with production of D.H.W. via storage tank
2 OFF Boiler with production of instantaneous D.H.W.
ON Position not available for this serie of boilers
3 OFF Heating pressure switch, disabled
ON Heating pressure switch, enabled
4 OFF EBM PAPST brand fan
ON Position not available for this serie of boilers
5 OFF Combination boiler for heating and D.H.W.
ON Boiler for heating only
6 OFF High temperature heating service, 86°F (30°C) to 176°F (80°C)
ON Low temperature heating service, 68°F (20°C) to 113°F (45°C)
7 OFF Boiler confi guration change, disabled
ON Boiler confi guration change, enabled
8 OFF Maximum heating supply water temperature of 176°F (80°C)
ON Position not available for this kind of boilers