Lochinvar knight 81-286 User Manual

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Service
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                       Service Manual
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Service 
General Operation
How the boiler operates
The Knight boiler uses an advanced stainless steel heat 
exchanger and an electronic control module that allows 
fully condensing operation.  The blower pulls in gas and air 
and pushes flue products out of the boiler through the heat 
exchanger and flue piping.  The control module regulates 
blower speed to control boiler firing rate.  The gas valve 
senses the amount of air flowing into the boiler and allows 
only the right amount of gas to flow.
How the control module operates
The Knight boiler control module receives input from 
boiler sensors.  The control module activates and controls 
the blower and gas valve to regulate heat input and switches 
boiler, DHW and system pumps on and off as needed.  
The user/installer programs the module to meet system 
needs by adjusting control parameters.  These parameters 
set operating temperatures and boiler operating modes.  
Boiler operation can be based on boiler outlet water 
temperature, boiler return water temperature or system 
supply temperature, depending on the parameter setting.
Sequence of operation
Table 1-1 shows control module normal sequences of 
operation for space heating and DHW operation.  The 
combined operation sequence is for a typical application, 
programmed to provide DHW priority.
Access modes
User
The user can adjust space heating and tank target temperatures 
by pressing the NAVIGATION dial when “SETPOINTS” is 
flashing at the bottom of the display.  The date and time, and 
the temperature units can also be changed.
Installer
Most parameters are available only to the installer, accessible 
only by entering the installer password (5309).
Saving parameters 
(reference the Parameter Table - 
Table 1-4 on pages 15 - 18 of this manual)
Please note that the brackets ([]) denote 
screen status.
 NOTICE
To save parameters and exit programming:
Press the RIGHT SELECT [SAVE] key and then press the 
RIGHT SELECT [HOME] key.
To enter a parameter and continue programming:
Press the RIGHT SELECT [SAVE] key 1 time to return to the 
parameter listings; press again to return to the menu listings.  
Remember to press the RIGHT SELECT [HOME] key when 
finished programming in order to save the changes made.