Slant/Fin VSL-160B, Installation Instructions Manual

Page: 71 / 108

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13.7 - Adjusting the
domestic hot water
temperature
The domestic hot water temperature
is adjusted by turning knob “11” shown
in Figure 13-1. When the knob is
turned, the display, item “1” in Figure
13-1, shows a flashing and the
temperature being selected. The range
within which the domestic hot water can
be set is 104°F (40°C) to 140°F (60°C)
or from 104°F (40°C) to 158°F (70°C)
when an indirect storage tank is used.
13.8 - Heating
system temperature
adjustment
The boiler provides hot water to the
heating system at the temperature
set by adjusting knob “7” as shown
in Figure 13-1. The room thermostat
turns the boiler’s circulator pump on
in order to satisfy the heat demand of
the rooms controlled by the thermostat.
To maximize the boilers’ performance,
temperature knob “7”, should be set at
a value that is just suffi cient to maintain
the desired temperature of the rooms. As
the weather gets colder, progressively
increase the water temperature by
adjusting knob “7”. When the weather
gets milder turn the water temperature
down. This extremely simple method
is suitable for the following types of
systems:
A - small systems with radiators where
the thermostat is installed in a room
whose temperature is characteristic
of all the other rooms;
B - large systems with radiators, where
each zone is controlled by its own
room thermostat. Where zone valves
are used the boiler pump is shutdown
only when all the room thermostats
are satisfi ed.
C - large systems with low temperature
radiant panels , where each zone is
controlled by its own room thermostat.
Where zone valves are used the boiler
pump is shutdown only when all the
room thermostats are satisfi ed.
13.9 - Heating
system type
selection
The boiler is factory set for wall stat
control as per Section 13.8.
The heating system type can be
changed by going to the “Installers’
Menu” in Section 13.17 and changing
the parameter. One of the
three following heating modes can be
selected:
-CH = 00 “Wall stat control”: follow
Section 13.8;
-CH = 01 “Outdoor reset control”:
follow Section 13.10 (an outdoor
temperature sensor is required);
-CH = 02 “Outdoor reset control with
room compensation control”:
follow Section 13.10.1 to 13.10.6
(an outdoor temperature sensor
is required):
13.10 - Outdoor
reset adjustment
While in the “Installers’ Menu”, set the
parameter to 01. In this mode
the heating supply water temperature,
calculated temperature in Figures 13-2
and 13-3, will be adjusted automatically
based on the input from the outdoor
temperature sensor. The relationship
between the outdoor temperature
and the supply water temperature,
corresponds with the graphs shown
in Figures 13-2 and 13-3. In order to
change the relationship between the
supply water temperature and the
outdoor temperature, all the parameters
listed in the sections below must be set.
13.10.1 - Outdoor reset
applications
Outdoor reset is a sophisticated way to
maximize comfort and boiler effi ciency.
It is suitable for the following system
types:
A - small systems, with radiators where
the thermostat is installed in a room
whose temperature is characteristic
of all the other rooms. The room
thermostat is used to turn the boiler
on and off.
B - Iarge systems, with radiators, where
each zone is controlled by its own
room thermostat. Where zone valves
are used the boiler pump is shutdown
only when all the room thermostats
are satisfi ed (see to an appropriate
electrical system).
C - small systems, with low tempera-
ture radiant panels where the
thermostat is installed in a room
whose temperature is characteristic
of all the other rooms. The room
thermostat is used to turn the boiler
on and off. In this type of system it is
necessary to consider that the radiant
panel systems sometimes have long
lag times.
D - Iarge systems with low temperature
radiant where each zone is controlled
by its own room thermostat. Where
zone valves are used the boiler pump
is shutdown only when all the room
thermostats are satisfi ed.
13.10.2 - Outdoor reset
adjustment precautions
When making adjustments to change
the supply temperature, it is advisable
to fi rst set the suggested default values
for the desired curves shown in fi gures
13-2 and 13-3. If these default values
do not produce a satisfactory result,
then proceed to make the appropriate
adjustments bearing in mind that:
A - each parameter must be very
gradually;
B - after each parameter change, wait
at least 24 hours in order to see the
result;
C - the closer the adjustment curve
matches the actual load of the
building, the greater the comfort and
the energy savings will be;
D - knob “7” in Figure 13-1 can be
used to make the small line shifts,
“b”, shown in Figure 13-3. These
shifts will change the supply water
temperature up to 18 °F
(10 °C) .
13 - USE