Knight WH- 286, Руководство по установке и эксплуатации

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Installation & Operation Manual
11
Operating information
Protection features
Outlet temperature, flue temperature, and
temperature rise limiting
The outlet temperature is monitored by the boiler outlet
temperature sensor. When the outlet temperature exceeds
185°F, the unit will reduce the fan speed. If the outlet water
temperature exceeds 195°F the control will shut the unit
down until it cools off.
The control module monitors the flue temperature by a
sensor located in the flue exhaust. If the flue temperature
exceeds 215°F the control will reduce the maximum fan
speed. If the flue temperature exceeds 240°F the control will
shut the unit down. The unit will restart automatically once
the flue temperature drops 25°F and the minimum off time
has expired.
The control monitors the temperature difference between
the inlet and the outlet sensor. If this difference exceeds
55°F the control will reduce the maximum fan speed. If
the temperature difference exceeds 60°F the control will
shut the unit down. The unit will restart automatically once
the temperature difference has dropped below 55°F and the
minimum off time has expired.
Freeze protection
DO NOT install the boiler in a room likely to freeze.
The following integral feature of the SMART SYSTEM
control module provides some protection for the boiler only
-- not for the system.
• The SMART SYSTEM control module provides
freeze-up protection as follows when the boiler
water temperature drops below 45°F:
• Below 45°F, the boiler and system pumps operate
constantly.
• Below 37°F, the boiler turns on.
• Boiler and pumps turn off if boiler water
temperature rises above 45°F.
• Lower temperatures may be programmed for
systems with anti-freeze solutions.
This feature of the SMART SYSTEM
control module does not eliminate the
possibility of freezing. The installation
must still use recognized design,
installation and maintenance practice to
prevent freeze potential for the boiler and
system.
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CAUTION
NOTICE
When system return temperatures
are maintained below the dew point,
condensation will form on the inside of
the boiler jacket causing some internal
sheet metal components to rust.
Low voltage blocking
The blower and gas valve require a minimum amount of
voltage in order to operate properly. If an ignition attempt is
made when the line voltage is temporarily low (such as during a
brownout), the control could enter a manual reset lockout. To
prevent this, the control monitors the voltage and blocks any
heat demands until the voltage returns to an acceptable level.
Monitor external limits
Connections are provided on the connection board for external
limits such as flow switch, low water cutoff, gas pressure
switches, and a louver proving switch. The SMART SYSTEM
will shut off the burner and inhibit relighting whenever any of
these external limits open.
Run-time and alarm outputs
The boiler provides dry contacts for indicating when the boiler
is running, and when it is unable to operate.
Run-time and cycle counting
The control uses two timers to monitor the total hours of
burner operation. One timer monitors the time the boiler is
firing in the Space Heating Mode. The other timer monitors
the time the boiler is firing in the DHW Mode.
The control uses two (2) ignition counters to monitor the
amount of boiler cycles. The first counter counts all ignitions
of the control. The second counter counts only ignition
attempts that have failed.
Service reminder
The control can be programmed for service reminder
notification. This notification will become active when either a
set time frame has expired, or a set amount of running hours or
cycles has expired (all adjustable by the installer). The display
will show a Maintenance Required screen. The installer's name
and phone number can be programmed into the control. This
information will appear on the Maintenance Required screen.
The service reminder notification can be reset or disabled by
the installer.
Error logging
The control will hold in memory the last 10 lockouts as well as
the last 10 blockings. The date and time of the occurrence will
be recorded as well. Only the 10 most current occurrences of
each will be held in memory.