Natco Fire Coil 85, Инструкция по установке и эксплуатации

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National Combustion Co., Inc.
Page 30
combustion air. Determine the cause, and correct.
Replace the burners in the reverse order
7.2.2 Filter
The filter used in the Fire Coil 85 is washable with
an 83% arrestance. Since the filter is washable, it will
only need replacement when unwashable, deteriorated or
damaged. If filter replacement is needed, it should only
be replaced with a factory part. Inspect the air filter. If
there is debris on the air filter, remove it from the filter
box, and wash it with mild soap and water. Ensure that
the filter is completely dry before re-installing, in reverse
order.
7.2.3 Gas Valves
The gas valves are designed to operate with supply
pressures of 4-13 inches w.c. (1.0 to 3.2 kPa).
To remove a valve, shut off 120-volt power and the
manual gas shutoff valve. Remove the top front panel from
the unit. Disconnect the wires to the valve. Disengage the
flanged fitting before and after the valve, and remove the
valve. Re-install in reverse order. Ensure o-rings are
properly installed for both inlet and outlet. Turn on manual
gas shutoff valve and 120 volt power and check appliance
operation and tightness of gas valve connections.
7.2.4 Manual Reset High Limit Control
The high limit switch is manual reset switch with an
adjustable set point, up to 240°F (116°C) on boiler
models and 200°F (93°C) on water heater models and
boilers ordered with low temperature controls. To
replace the switch, shut off the 120-volt power to the
appliance. Remove the cover from the switch to access
the mounting screws. Remove the screws, and pull the
switch off the control panel. Remove the capilliary and
bulb from the thermal well located in the header.
Replace in reverse order.
7.2.5 Temperature Control
The temperature control is a Honeywell L6008. To
replace the control, shut off the 120-volt power to the
appliance. Remove the cover from the control panel, and
remove the mounting screws to remove the controller.
Replace in reverse order.
7.2.6 Ignition Controls
The ignition controls ensure the proved interrupted-
type ignition system. They control the hot surface
ignitors and prove that the flame signal is appropriate for
powering the gas valves. It also controls the blower’s
pre-purge and post-purge. Fire Coil 85 sizes 500 and
750 have one ignition control. Sizes 1000 to 2000 have
two ignition controls. On sizes up to 750, one ignition
control controls stages 1 and 2. On unit sizes 1000–
2000, one ignition control is for stage 1, and the other is
for stage 2.
To replace a control, shut off the 120-volt power to
the appliance. Remove the cover from the control panel.
Remove the electrical connectors from the ignition control.
Take out the controller’s mounting screws, and pull the
controller out. Replace in reverse order.
7.2.7 Ignitors/Sensor
The ignitor/sensor used are 120v "hot surface"
type. They are energized whenever there is a call for
heat and switched off when ignition is established and
flame has been sensed. Fire Coil 85 sizes 500 and 750
have one ignitor/sensor. Sizes 1000 to 2000 have two
ignitor/sensors. To replace the ignitor/sensor, shut off the
120-volt power to the appliance, remove the ignitor
access panel, disconnect the Molex connector, remove
the two mounting screws on the ignitor/sensor flange and
pull the ignitor out. ((Hot Surface) Ignitor and the Flame
Sensor are the same items). Install in reverse order,
always using a new ignitor gasket with the replacement
ignitor.
Caution
Ignitor gets hot.
7.2.8 Transformer
The transformer is not capable of supplying control
voltage for external devices such as zone valves, which
must have their own separate power supply. Should a
transformer need replacing, shut off the 120-volt power.
Unplug the transformer wires, remove the mounting
screws and remove the transformer. Replace transformer
in the reverse order.
7.2.9 Blowers
The combustion air blowers bring the combustion
air for the Fire Coil 85 from the upper chamber to the
lower chamber. Mixing of the gas and air occurs in the
burners. Sizes 500, 750 and 1000 each have one blower,
and sizes 1250 to 2000 each have two blowers. If a
blower change is required, turn off the 120-volt power
and gas supply to the unit. Remove the front panel.
Disconnect the blower's wire harness. Remove the
screws at the blower flange, and pull the blower out.
Replace blower in reverse order, ensuring that all joints
are made correctly. After replacement, ensure that the
unit operates properly, by following the set-up procedure
in this manual.
7.2.10 Flow Switch
The Fire Coil 85 uses a paddle-type flow switch to
ensure that the unit has water flow before ignition is
allowed.
7.2.11 Heat Exchanger Coil
WARNING
Black carbon soot buildup on a dirty heat exchanger
can be ignited by a random spark or flame, thereby
creating a risk of fire or explosion.. To prevent this
from happening, dampen the soot deposits with a wet