tekmar 274 Boiler Control - Manual (Page 26)

© 2012 274_D - 11/12 26 of 44
Rotate / Off
Use the Rotate / Off DIP switch to enable the Equal Run
Time Rotation feature. This feature Changes the firing
order of the boilers in order to maintain a similar amount of
running time on each boiler. If set to Off, the firing sequence
if fixed starting with boiler 1 to boiler 4.
Demands
Setback
Off
EMS
Rotate
Fixed Last
Pump Sequencer
Exercise
Off
Fixed Lead
First On / Last Off
First On / First Off
Pump Sequencer / Off
Use the Pump Sequencer / Off DIP switch to activate
primary pump sequencing. DHW operation is not available
when Pump Sequencer is selected.
If set to Pump Sequencer, the control operates primary
pumps 1 & 2 in stand-by mode.
If set to Off, the control operates primary pump 1 and the
pump 2 relay is then available for a DHW pump.
Demands
Setback
Off
EMS
Rotate
Fixed Last
Pump Sequencer
Exercise
Off
Fixed Lead
First On / Last Off
First On / First Off
Fixed Last / Off
Use the Fixed Last / Off DIP switch to exclude the last boiler
in the rotation sequence. This DIP is only active when the
Rotate / Off DIP is set to Rotate.
If set to Fixed Last, the last boiler is always the last to fire.
Fixed Last will only work for boilers wired to the Relay 4
terminals (13 and 14).
Demands
Setback
Off
EMS
Rotate
Fixed Last
Pump Sequencer
Exercise
Off
Fixed Lead
First On / Last Off
First On / First Off
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Fixed Lead / Off
Use the Fixed Lead / Off DIP switch to exclude the first
boiler in the rotation sequence. This DIP is only active
when the Rotate / Off DIP is set to Rotate.
If set to Fixed Lead, the first boiler is always the first to fire.
Fixed Lead will only work for boilers wired to the Relay 1
terminals (7 and 8).
Demands
Setback
Off
EMS
Rotate
Fixed Last
Pump Sequencer
Exercise
Off
Fixed Lead
First On / Last Off
First On / First Off
First On / Last Off or First On / First Off.
The First On / Last Off or First On / First Off DIP switch
selects whether the first boiler is the first to fire and the
last to shut off or the first to fire and the first to shut off.
This DIP switch is only active when the Rotate / Off DIP
switch is set to Rotate and the Fixed Lead / Off DIP switch
is set to Fixed Lead.
Demands
Setback
Off
EMS
Rotate
Fixed Last
Pump Sequencer
Exercise
Off
Fixed Lead
First On / Last Off
First On / First Off
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