Dettson HYDRAI016-208-3, Installation Instructions And Owner'S Manual

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Figure 2 – Power Stealing Thermostat Resistance
2.6.3 Thermostat Connection
Single Heating Zone
Connect the low voltage thermostat to R-W terminals
located inside the control panel.
Multiple Heating Zone
Connect the contacts of the motorized valves or pump
controls to R-W terminals inside the control panel.
2.6.4 Outdoor Sensor Connection
Mount the sensor on an outside wall, protected from
direct sunlight, so that it will accurately measure the
outside temperature. Install 2 #20 wires between the
outdoor sensor and the terminals identified as
EXT1
and
EXT2
inside the control panel of the boiler. This sensor
will allow the boiler to modulate its set point according to
the outdoor temperature, as per figure 5.
3 OPERATION
3.1 ADJUSTMENTS AND
START-UP
CAUTION
The boiler must be filled with water and all air purged
from the system, before turning on the power.
If
the power is turned on before the boiler is filled with
water, the elements will become seriously damaged.
Warranty will be void.
1. Turn the power on.
2. Adjust the set point of the boiler on the electronic
control. See the electronic control section for
adjustments.
3. Set the thermostat at 30°C (85°F). The circulator
should start as well as the electrical elements in
sequence with a 15 seconds delay, if CMD displays
100% (see section 3.7.1).
4. The circulator stays on for as long as there is a
call for heat except if differently configured on the
electronic control, as explained in section 3.7.2.
3.2 MECHANICAL HIGH LIMIT
The two mechanical limit aquastats (big black knobs)
must be set 30°F above the set point.
The aquastat
labeled "high limit" will deactivate the upper contactors.
The aquastat labeled "control" will deactivate the lower
contactors.
3.3 Quiet Mode
To make the boiler quieter, in the installer menu, choose
noise mode to low.
The low noise option reduces
the switching frequency of the contactors. This option
shall be used only in installation areas where noise is
problematic.
The normal mode allows the boiler to reach the
temperature setpoint more precisely, optimizing the
energy consumption. Preferably, use normal mode.
3.4 Load-Shedding
When a jumper is connected between D1 and D2
terminals, the boiler will reduce the maximum power
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