Make sure you have the right control – LAARS M4-LHS - Installation Manual User Manual
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M4-LHS installation and Operation Manual
9
Setback or Day/Night Scheduling
Two Setback modes are available for the M4-LHS:
• The Day/Night Scheduling provides an adjustable time-based schedule for the Setback (only available when Shutdown or Tstat is
selected as the Setback/Shutdown Startup option). See "Shutdown/Tstat/Setback Mode" on page 24.
• The Setback mode uses an external signal to switch the operation of the M4-LHS in and out of setback mode (only available when
Setback is selected as the Setback/Shutdown Startup option).
remote Set point (EMS 4-20ma)
By connecting the control to the optional 4-20mA EMS Interface (X-SIG), the control shall be capable of accepting a remote set point.
BaCnet MS/TP Communication
An optional BACnet Interface Module (X-BAC) (CA009100) can be used to connect the control to a BACnet MSTP network for remote
access.
MakE SurE YOu HaVE THE rigHT CONTrOL
If you need the M4-LHS to do additional tasks that either are not listed or do not know how to configure them, contact your local
Laars representative.
Setting an Initial Program will ease the configuration of the M4-LHS and will give the opportunity to utilize many of the energy saving
features while giving comfortable heat when needed.
The program should consist of the following:
• Selecting the features that your system can utilize.
• Installation: Install the Control, switches and sensors. See"Installation" on page 10
• Setting the System Startup. See "Startup Settings" on page 19.
• Setting the System Operating Settings. See "Operating Settings" on page 27
• Setting the Stages. See "Modulating Boiler Operating Settings" on page 33. Also, see "Staging Boiler Operating Settings" on page 34
• Adjusting Reset Ratio and Water Offset (In Reset Mode Only). See "Reset Ratio" on page 27