LAARS M4-LHS - Installation Manual - Manual (Page 23)

HT# 059295-00
A
M4-LHS installation and Operation Manual
23
MODuLaTiNg BOiLEr SETTiNgS
Boiler Number
Adjustable from 1 to 15 Default: 1
Button: MENU/<System Startup>/Boiler Type/.../Boiler Number
• Select the number of modulating boilers.
Modulating Output Type
4-20mA, 0-10V, 1-10V (Custom) Outputs Default: 1-10v Custom
Button: MENU/<System Startup>/..../Boiler Number/Output A Type
• The M4-LHS will offer the capability of controlling a variety of modulating signals.
Each boiler can be configured to have a different modulating signal. Check the boiler to
determine its signal requirements.
• When using the Extension, connect it to the M4-LHS prior to configuring the Output Type.
Otherwise, the M4-LHS might not recognize the Extension stages.
Modulating Mode
Normal, Parallel Default: Normal
Button: MENU/<System Startup>/..../Output A Type/Modulating Mode
• Some modulating boilers perform better at higher modulation. For these units, it is
advantageous to run one unit at high modulation than several units at lower modulation. If
the units used are of this type, select Normal. This is the recommended setting for typical
steel and cast iron boilers or boilers with low turndown ratios.
• There are many condensing boilers that run more efficiently at lower modulation. If it
is more energy efficient to run several units at lower modulation than one at high, select
Parallel. This is typically used on condensing boilers or boilers with high turndown ratios.
• For best Parallel performance, set the Modulation Start % to be equivalent to the lowest
firing rate of the boiler multiplied by 2. That is, if the lowest firing of the boiler was 20%,
set your Modulation Start% to 40%. See "Modulation Start %" on page 40.
• Set the Lag Delay to 0 for better parallel performance. See "Lag Delay" on page 33.
WarNiNg
Make sure that boiler modulation
wiring matches the signal selected.
Warranty will not cover failed
components caused by improper
wiring. See "Wiring the Boilers" on
page 14.
-- BOILER NUMBER --
2
[ ]
BACK ▲ ▼ SAVE
- MODULATING MODE -
Normal
Parallel
BACK ▲ ▼ SAVE
OUTPUT A TYPE --
4-20mA
0-10volt
0-5volt
2-10volt
1-5volt
BACK ▲ ▼ SAVE