LAARS Heating Systems
Page 46
fig. 51 – lead/lag activity in a multi-Boiler
System
Low demand -
The first burner* in
sequence fires at
less than 65%
First
burner*
Second
burner*
Third
burner*
Fourth
burner*
Boiler X
Boiler Y
Demand increases -
Once the first burner
reaches 50%,
the second burner*
switches on, and
both modulate
together between 29%
and 65%
Demand increases -
Once the first two
burners reach 65%,
the third burner*
switches on, and all
three modulate together
between 29% and 65%
Nearing max. demand -
The fourth burner* is
active. Once all four
reach 65%, all are
allowed to go over
65%
* - The Lead/Lag controller will change the firing order of the
burners, based on the run time of each burner.
9.1.3
ntH lead/lag with Indirect
Domestic Hot Water
So far, we have been describing a system which
handles the Central Heat function only. There are
several ways the Domestic Hot Water can be set up
on a Lead/Lag system. For a detailed description,
see Section 9.5.
9.2
Connection terminals
Figure 52 shows some of the connection terminals
on the circuit board inside the cabinet.
WarnInG
Before connecting or disconnecting any wiring
inside a boiler, be absolutely sure to turn off all
electrical power to the unit. Failure to do this
could result in property damage, serious injury or
death.
Summary of Contents for NTV1000
Page 2: ......
Page 35: ...NeoTherm Boilers and Water Heaters Page 31 Fig 20 Ladder Diagram...
Page 36: ...LAARS Heating Systems Page 32 Fig 21 Wiring Diagram...
Page 37: ...NeoTherm Boilers and Water Heaters Page 33...
Page 51: ...NeoTherm Boilers and Water Heaters Page 47 Fig 52 Connection Terminals...
Page 130: ...LAARS Heating Systems Page 126 Fig 140 Machine Frame and Rear Panel 13 3 PARTS ILLUSTRATIONS...
Page 131: ...NeoTherm Boilers and Water Heaters Page 127 Fig 141 Front Panel and Covers...
Page 132: ...LAARS Heating Systems Page 128 Fig 142 Burners and Combustion Chambers...
Page 134: ...LAARS Heating Systems Page 130 Fig 145 Electronic Components...
Page 135: ...NeoTherm Boilers and Water Heaters Page 131 Fig 146 Condensate Trap Fig 147 Control Bezel...
Page 136: ...LAARS Heating Systems Page 132 Fig 148 Flow Switch...
Page 137: ...NeoTherm Boilers and Water Heaters Page 133 This page intentionally left blank...