LP-517 Rev. 000 Rel. 019 Date 7.21.20
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G. Outdoor Sensor
NOTE:
There is no connection required if an outdoor sensor is not
used in this installation.
1. If using an outdoor sensor, connect wires for sensor to the
terminals marked 12 and 13 (OUTDOOR SEN, shown in Figure 22)
in the electrical junction box. Caution should be used to ensure
neither of these terminals becomes connected to ground.
2. Use a minimum 22 AWG wire for runs of 100 feet or less and
minimum 18 AWG wire for runs of up to 150 feet.
3. Mount the outdoor sensor on an exterior surface of the building,
preferably on the north side in an area that will not be affected by
direct sunlight and will be exposed to varying weather conditions.
H. Indirect Sensor
NOTE:
There is no connection required if an indirect water heater is
not used in this installation.
1. The boiler will operate an indirect fired water heater with either
a thermostat type aquastat installed in the indirect tank, or an HTP
7250P-325 tank sensor. When a tank sensor is used, the control will
automatically detect its presence and a demand for heat from the
indirect water heater will be generated when the tank temperature
falls below the user selected set point by more than the user selected
offset. The demand will continue until the sensor measures that the
indirect water heater temperature is above the set point.
2. Connect the indirect tank sensor (7250P-325) to the terminals
marked 10 and 11 (DHW SENSOR, shown in Figure 22) in the
electrical junction box.
Failure to use the correct sensor may result in tank
temperature being either above or below set point, and
could result in decreased performance, substantial property
damage, or heightened risk of injury or death due to scalds.
Caution should be used to ensure neither of these terminals
becomes connected to ground.
NOTE:
If sensor wires are located in an area with sources of
potential electromagnetic interference (EMI), the sensor
wires should be shielded, or the wires routed in a grounded
metal conduit. If using shielded cable, the shielding should be
connected to the common ground of the boiler.
2. Mount the thermostat on an inside wall as centrally as possible
to the area being heated, but away from drafts or heat producing
devices such as television sets that could influence the ability of the
thermostat to measure room temperature.
3. If the thermostat is equipped with an anticipator and it is
connected directly to the boiler, the anticipator should be set at .1
amps. If the thermostat is connected to other devices, the anticipator
should be set to match the power requirements of the device it is
connected to. See the instruction manual of the connected devices
for further information.
I. Optional 0-10 Volt Building Control Signal
1. A signal from a building management system may be
connected to the boiler to enable remote control. This signal
should be a 0-10 volt positive-going DC signal. When this input
is enabled using the installer menu, a building control system
can be used to control the set point temperature of the boiler.
The control interprets the 0-10 volt signal as follows; when
the signal is between 0 and 1 volts, the boiler will ignite. As
the signal continues to rise towards its maximum of 10 volts,
the boiler will increase in either set point temperature or firing
rate depending on the setting of function 17 in the Installer
Menu. See this manual for details on the setting of function
16 and 17 for this option.
2. Connect a building management system or other auxiliary
control signal to the terminals marked 17, 0-10 VOLT + and 16,
Figure 23 - Boiler Manifold
0-10 VOLT – in the electrical
junction box (shown in Figure
22). Caution should be used
to ensure that the 0-10 VOLT +
connection does not become
connected to ground.
J. Optional High Gas
Pressure Switch
1. If an optional high gas
pressure switch is used, it
should be installed on the
outlet side of the gas valve.
This is normally closed and
will open if the pressure goes
above 20” w.c. on the outlet
side.
2. Locate the two pigtails
hanging from the electrical
box inside of the boiler
cabinet. Remove and discard
the jumper plug from one of
the unused pigtails.
3. Connect the high gas
pressure switch to the pigtail
that you removed the jumper plug from.
K. Optional Low Gas Pressure Switch
1. If an optional low gas pressure switch is used, it should be installed
on the inlet side of the gas valve. This is normally closed and will open
if the pressure goes below 1” w.c. on the inlet side.
2. Locate the two pigtails hanging from the electrical box inside of the
boiler cabinet. Remove and discard the jumper plug from one of the
unused pigtails.
3. Connect the low gas pressure switch to the pigtail that you removed
the jumper plug from.
