LAARS M4-LHS - Installation Manual - Manual (Page 22)

HT# 059295-00
A
22
M4-LHS installation and Operation Manual
HYBriD MODuLaTiNg BOiLEr SETTiNgS
Modulating Output Type
4-20mA, 0-10V, 1-10V (Custom) Outputs Default: 1-10v Custom
Button: MENU/<System Startup>/..../Condensing Boiler Number/Output A Type
• If either of the Condensing or Non-Condensing Boiler groups was set to Modulating as the
Boiler 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.
• The modulating output for each boiler can be configured to 4-20mA operation (Current) or
any of the voltage options. 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/Condensing 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 boilers
with low turndown ratios.
• Most condensing boilers run more efficiently at lower modulation. If it is more energy
efficient to run several units at lower modulation than one at high. In this case 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.
CONDENSING
-- OUTPUT A TYPE --
4-20mA
0-10volt
0-5volt
2-10volt
1-5volt
BACK ▲ ▼ SAVE
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.
CONDENSING
- MODULATING MODE -
Normal
Parallel
BACK ▲ ▼ SAVE
NON-CONDENSING
- MODULATING MODE -
Normal
Parallel
BACK ▲ ▼ SAVE
HYBriD STagiNg BOiLEr SETTiNgS
Staging Output Type
On/Off, 2-Stage, 3-Stage, 4-Stage Outputs Default: On/Off
Button: MENU/<System Startup>/..../Non-Condensing Output Type
• The M4-LHS can sequence multi-stage boiler starting with a single On/Off and up to a
4-stages. Just select the number of stages per boiler from this menu option.
• For each boiler stage a single output relay will be used. That is a 2-stage boiler will use two
of the control stages.
• The number selected applies to all sequencing boilers within that group whether it is
Condensing or Non-Condensing.
• The maximum number of stages the control can operate is 4. But with the addition of up to
two extensions, it can handle up to a total of 16 stages.
NON-CONDENSING
-- OUTPUT TYPE --
On/Off
2-Stage
3-Stage
4-Stage
BACK ▲ ▼ SAVE
Staging Mode
Lo/Hi/Lo/Hi, Lo/Lo/Hi/Hi Default: Lo/Hi/Lo/Hi
Button: MENU/<System Startup>/..../Non-Condensing Output Type/Non-Cond Staging Mode
• During low load conditions, some boilers run more efficient when the lower stages are
energized alone than with the higher stages. For these types of boilers select Lo/Lo/Hi/Hi.
Then, the M4-LHS will sequence the lower stages of all boilers set to Auto before
sequencing the higher stages.
• For the rest of the boiler types, the Lo/Hi/Lo/Hi should allow the staging of the lower stage
of the lead boiler followed by the higher stage of the same boiler. Then when more stages
are needed, it will fire the lower stage of the lag boiler followed by the higher stages
NON-CONDENSING
- STAGING MODE -
LO/HI/LO/HI
LO/LO/HI/HI
BACK ▲ ▼ SAVE