Operating settings, Program change switch setting, Season – LAARS M4-Ext - Installation Manual User Manual
Page 22: Reset ratio, Offset, Mini-mod, Alert, A b c d, Laars heating systems, System
22
OPERATiNg SETTiNgS
PROgRAM CHANgE SWiTCH SETTiNg
To be able to change the M4-CNC settings, the Program/Run Switch must be set to Program.
The switch is located under the Enclosure Wiring Cover for security. The Enclosure Wiring
Cover can be securely closed using a lock.
SYSTEM
A
B
C
D
Full Modulation Sequencing Control
1 2
RUN
PROGRAM
FOR ALL CIRCUITS
120VAC, 6A RESISTIVE
OUTPUT RATINGS:
1A PILOT DUTY, 15A TOTAL
115VAC 60Hz , 12VA MAX
INPUT RATINGS:
USE COPPER CONDUCTORS ONLY
DO NOT APPLY ANY VOLTAGE
TO INPUT TERMINALS
3 4 5 6 7 8 9 10 11 12
13
15
14
17
16
18
22
20
19
21
24
23
29
25
27
26
28
32
30 31
L N
-
+
+
T
T
O
O
RS-485
mA
GND
VLT
SYS
A
B
C
D
PWR
CUR / VLT
A
-
+
+
mA
GND
VLT
-
+
+
mA
GND
VLT
-
+
+
mA
GND
VLT
+
mA
TEMP
OUTDOOR
O
O
TEMP
SYSTEM
EXTENSION
MODULE
CUR / VLT
B
CUR / VLT
C
CUR / VLT
D
CAUTION
: RISK OF ELECTRIC SHOCK
More than one disconnect switch may be required
to de-energize the equipment before servicing.
PROVE
/DHW
SHUTDOWN
/TSTAT
/SETBACK
ENCLOSED
ENERGY
MANAGEMENT
EQUIPMENT
99RA
Mini-MOD
SEASON
Winter, Summer
Default: Winter
Button: MENU/Season
• The M4-CNC will turn all boiler relays off when it is in Summer setting. However, a DHW
call will bring boilers back on if needed. The Message Display Line will display Summer to
show the status.
• When in Winter, the M4-CNC will activate the System relay whenever the Outdoor
temperature (OD) falls below the Outdoor Cutoff setting. The Message Display Line will
not display any season information when in Winter.
• When the heating season is over, it is a good practice to switch the M4-CNC to Summer
setting. This will allow DHW calls to operate the boilers when needed.
----- SEASON -----
Winter
Summer
BACK ▲ ▼ SAVE
ALERT
DO NOT turn power off to the
M4-CNC when heating season
is over. If you do so, the battery
will run down and will have to
be replaced. Instead, switch to
Summer.
RESET RATiO
Adjustable 1.00ºOD : 4.00ºSys to 4.00ºOD : 1.00ºSys
Default: 1.00ºOD : 1.00ºSys
Button: MENU/Set Point
• The Reset Ratio determines how the System water temperature (SYS) will vary with
Outside temperature (OD). With any of the ratios, the colder it becomes outside, the hotter
the temperature of the system water. The ratios are adjustable from 1.00 (OD):4.00 (SYS) to
4.00 (OD):1.00 (SYS). See "Outdoor Reset Concept" on page 7.
• With a 1.00 (OD):4.00 (SYS) ratio, the System water temperature (SYS) will increase
rapidly as the outside temperature falls, hitting the maximum of 240°F at 24°F outside
temperature. With a 4.00 (OD):1.00 (SYS) ratio, the System water temperature (SYS) will
increase slowly as the outside temperature falls. Even at -30°F, the system water will only
be 125°F, and at 24°F outside, the system water will be 112°F. Such a low Reset Ratio
might be used with radiant floor heating applications.
• With most baseboard heating applications, a 1.00 (OD):1.00 (SYS) setting is a good place to
start. With a 1.00 (OD):1.00 (SYS) ratio, for every degree the outside temperature falls, the
system water temperature is increased one degree.
• If required: Adjust the RESET RATIO in cold weather. If the ambient building
temperatures are too cold in cold weather, move the ratio to a higher selection. That is,
if 1.00 (OD):1.00 (SYS) was initially selected, change the selection to 1.00 (OD):1.25
(SYS). If the building temperatures are too warm in cold weather, move the ratio to a lower
selection. That is, if 1.00 (OD):1.00 (SYS) was initially selected, change the selection to
1.25 (OD):1.00 (SYS).
-- SYSTEM TARGET --
1.00
o
OD = 4.00
o
Sys
1.00
o
OD = 3.00
o
Sys
1.00
o
OD = 2.00
o
Sys
1.00
o
OD = 1.50
o
Sys
1.00
o
OD = 1.25
o
Sys
1.00
o
OD = 1.00
o
Sys
1.25
o
OD = 1.00
o
Sys
1.50
o
OD = 1.00
o
Sys
2.00
o
OD = 1.00
o
Sys
3.00
o
OD = 1.00
o
Sys
4.00
o
OD = 1.00
o
Sys
BACK ▲ ▼ SAVE
Outdoor Temperature
W
at
er
T
em
pe
ra
tu
re
70
40
50
60
130
120
110
100
Outdoor Temperature
W
at
er
T
em
pe
ra
tu
re
70
40
50
60
110
100
90
80
Outdoor Temperature
W
at
er
Te
m
pe
ra
tu
re
70
40
50
60
150
140
130
120
1:4
With a 0° Offset, the
Reset curves begin at
100° Water Temperature.
With a -20° Offset, the
Reset curves begin at
80° Water Temperature.
With a +20° Offset, the
Reset curves begin at
120° Water Temperature.
1:4
1:4
1:1
1:1
1:1
4:1
4:1
4:1
90
100
+20 Offset
-20 Offset
Outdoor Temperature
W
at
er
T
em
pe
ra
tu
re
70
40
50
60
130
120
110
100
1:4
1:1
4:1
Colder
Warmer
OFFSET
Adjustable from 50Fº/28Cº to -50Fº/-28Cº
Default: 0Fº/0Cº
Button: MENU/Set Point/Offset
• The Offset setting lets you adjust the starting points of the Reset Ratio curves. This means
that, regardless of the Outdoor temperature (OD), or the Reset Ratio that has been selected,
when the Offset setting is changed, that change is directly added to or subtracted from the
calculated temperature. For example, if the Set Point temperature was 130°F and the Offset
was changed from 0F° to 10F° (an increase of 10F°), then the Set Point temperature would
increase to 140°F
------- OFFSET ------
+0
o
F
[ ]
BACK ▲ ▼ SAVE
LAARS Heating Systems
HT# 059104-00 B