Knight WH- 286, Руководство по установке и эксплуатации

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Boiler temperature regulation
Operating temperature (target)
The SMART SYSTEM control module senses water
temperature and regulates boiler firing and firing rate to
achieve a target temperature. The target temperature can be
set between 32°F and 190°F.
• Target temperature is calculated as described in the
“Outdoor Reset Operation” section, when the
outdoor sensor is connected.
• If the outdoor sensor is not connected, the target
temperature is fixed at SH (1 - 3) set points. An
outdoor sensor fault will remain on the display
screen until the outdoor sensor is reconnected.
High limit operations
The Knight Wall Hung Fire Tube boiler is equipped with
adjustable automatic reset and manual reset high limits. The
automatic reset high limit has a maximum set point of 200°F
and the manual reset high limit has a maximum set point of
210°F.
When the outlet temperature exceeds 200°F, the automatic
high limit action occurs. The boiler shuts down until the
outlet water temperature cools below 190°F, and a 60 second
timer has expired. If the outlet temperature continues to
increase, the manual reset high limit action will occur at
210°F.
High limit test procedure
1. Turn ON the main power to the boiler by placing the
ON/OFF switch in the ON position.
2. From the Status Screen, press the NAVIGATION dial to
access the Set Points Screen.
3. Press the LEFT SELECT (LIMITS) key.
4. Select the manual reset high limit (MRHL) by rotating
the NAVIGATION dial counterclockwise, then press
the NAVIGATION dial.
5. Decrease the set point of the MRHL to below the current
outlet temperature (or to its minimum setting, whichever
is higher) by turning the NAVIGATION dial
counterclockwise.
6. Press the RIGHT SELECT [SAVE] key.
7. Press the RIGHT SELECT [HOME] key. The new
parameter will upload to the control.
8. If the current outlet temperature is above the new MRHL
set point, the MRHL will function causing boiler lockout.
If this occurs, skip to Step 11.
11
Operating information
(continued)
9. If the current outlet temperature is below the new MRHL
set point, locate the pinhole (SERVICE button) above the
RESET button on the display board. Insert a thin probe
(such as a paper clip) into the hole and press the button
continuously for five (5) seconds to place the boiler into
Service Mode. In Service Mode, the boiler will fire at
ignition speed and will then modulate up to full fire.
10. Once the outlet temperature rises up to the MRHL set
point, the MRHL will function, causing the boiler to shut
down and lock out.
11. Repeat Steps 2 - 7 to adjust the MRHL to its normal
settings.
Low water cutoff protection
1. The SMART SYSTEM control module uses temperature
sensing of both supply and return areas of the heat
exchanger. If the flow rate is too low or the outlet
temperature too high, the control module modulates and
shuts the boiler down. This ensures boiler shutdown in the
event of low water or low flow conditions.
2. Some codes and jurisdiction may accept these integral
features of the control in lieu of requiring an additional
limit control or low water cutoff. Consult local jurisdiction
to determine. A low water cutoff is available from the
factory (#100208651).
Outdoor reset operation
Target temperature with outdoor reset
This feature improves the system's efficiency by decreasing
set point as the outdoor temperature increases. For boilers
with input rates less than 300,000 Btu/hr Energy Efficiency
Standards require the use of a control that automatically
adjusts set point in relation to heat demand. In the absence
of an external energy management system, this feature MUST
BE used.
See the Knight Wall Hung Fire Tube Boiler Service Manual to
change the settings.
Reset curve
The reset curve looks at outdoor air temperature and adjusts
the set point in relation to heat demand.
Please note that the brackets ([]) denote
screen status.
NOTICE
Installation & Operation Manual
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