Laars LMH, Installation And Operation Instructions Manual, Page: 2 / 52

LAARS Heating Systems
TABLE OF CONTENTS
SECTION 1.
General Information
1.1 Introduction ........................................................ 2
1.2 Rating Plate ........................................................ 2
1.3 Model Nomenclature........................................... 2
1.4 Start Up / Shut Down Instruction (Decal) ............ 3
1.5 Unpacking ........................................................... 3
1.6 Warranty ............................................................. 3
1.7 Product Overview ............................................... 4
1.8 Dimensions ......................................................... 5
SECTION 2.
Locating the Appliance
2.1 Locating the Appliance........................................ 6
2.2 Locating Appliance for Correct Vent Distance
from Outside Wall or Roof Termination ............... 6
SECTION 3.
Venting and Combustion Air
3.1 Combustion Air ................................................... 8
3.1.1 Combustion Air from Room................................. 8
3.1.2 Ducted Combustion Air ....................................... 8
3.2 Venting (Exhaust) ............................................... 9
3.3.1 Side Wall Vent Terminal .................................... 10
3.3.2 Side Wall Combustion Air Terminal ................... 10
3.3.3 Vertical Vent Terminal ....................................... 10
3.3.4 Vertical Combustion Air Terminal ...................... 10
3.3.5 Installations in the Commonwealth
of Massachusetts .............................................. 12
3.4 Common Vent Test ........................................... 12
SECTION 4.
Gas Supply and Piping
4.1 Gas Supply and Piping .......................................... 14
SECTION 5.
Pump Capacity
5.1 Mascot II Heating System Pump Capacity ............ 15
SECTION 6.
Water Connections
6.1 Central Heat System Piping.............................. 15
6.2 Cold Water Make-Up ........................................ 15
6.3 Freeze Protection ............................................. 16
6.4 Suggested Piping Schematics .......................... 17
6.5 Recognized Chemicals ..................................... 17
6.6 Domestic Hot Water (DHW) Piping (LMC) ........ 17
6.7 Condensate Drain ............................................. 17
SECTION 7.
Electrical Connections
7.1 Main Power ....................................................... 23
7.2 Pump Connections ........................................... 23
7.3 24Vac Transformer Circuit Breaker ................... 23
7.4 Central Heat - Call for Heat .............................. 23
7.5 Outdoor Air Temperature Sensor ...................... 23
7.6 Domestic Hot Water Connection ...................... 23
7.7 System Sensor
(lead lag/cascading operation only) .................. 23
7.8 External Control Connections ........................... 23
7.9 Lead Lag / Cascading Wiring Connections....... 23
7.10 Wiring Diagrams ............................................... 24
SECTION 8.
Control Setup and Operation
8.1
USER INTERFACE and
Digital Display Navigation
............................. 26
8.2 Ignition Control - Sequence of Events .............. 26
8.3 Modulation Control............................................ 27
8.4 Pump Control .................................................... 27
8.5 High Limit .......................................................... 27
8.6 Stack Temperature ............................................ 27
8.7 Domestic Hot Water Temperature..................... 27
8.8 Lead Lag / Cascading ........................................ 27
8.8.1 Lead Lag Setpoint............................................. 27
8.8.2 Lead Lag Master / Slave Selection ................... 27
8.8.3 Lead Lag Address ............................................. 27
8.8.4 Lead Lag Hysteresis ......................................... 27
8.8.5 Lead Lag Base Load Setting ............................ 27