Weil-McLain WM97+110, Manual, Page: 77 / 132

Part number 550-142-085/0712
– 77 –
WM97+
gas
-
fired water boiler
— Boiler Manual
HEAT SETTINGS menus
(continued)
4. Boost will continue until the setpoint (target temperature)
reaches the MAX SUPPLY setting.
5. The purpose of boost is to compensate for changes in demand
not addressed by the reset curve. Typically, set boost to 30
minutes. The factory default is “OFF” — that is, boost is not
enabled with default settings.
PRE PUMP TIME
1. The boiler circulator and zone circulators (if activated with
the WM97+ zone circulator outputs) will start this amount
of time before the burner is started.
POST PUMP TIME
1. The boiler circulator and zone circulators (if activated with
the WM97+ zone circulator outputs) will continue this
amount of time after the burner is shut down when the call
for heat is satisfied.
MIN RATE / MAX RATE
1. Use to set minimum and maximum boiler inputs by setting
minimum and maximum blower RPM.
2. This adjustment can be used to match the maximum boiler
output the maximum heat load. This will reduce boiler cycling
and increase boiler/system efficiency.
During combustion testing
, the Maximum rate
must be set to the Maximum Rate “High Value” listed
in Figure 85 to allow the boiler to be set to maximum
input during high-fire set-up and testing.
Figure 85
HEAT SETTINGS
menus (see Figure 80, page 72 for access information)
Menu/Item Units
Low
Value
High
Value
Default Comment
System Type Types Off Custom FTB
Boiler Circulator Spd Selection Off High Med Select speed or select OFF to deactivate boiler during
space heating call
Max Supply °F 60 190 180 Boiler enters manual reset lockout at 200°F
Min Supply °F 60 190 130 N/A - DHW does not use reset
Max Outdoor °F 50 100 70 N/A - DHW does not use reset
Min Outdoor °F –20 50 0 N/A - DHW does not use reset
Modulate On Diff °F 2 10 5 Boiler turns on if temperature drops below target minus
differential on
Modulate Off Diff °F 2 10 5 Boiler shuts down if modulates past target plus differential
off
Min On Time minutes off 240 30 Shortest time boiler will satisfy space heating system
before switching to DHW
Boost Interval minutes off 240 off When operating on ODR increases target 10°F when this
time expires until reaching MAX
Prepump Time: ###
SEC seconds 0 240 20 Additional time to run circulators longer than standard 10
second time
Postpump Time: ###
SEC seconds off 240 30 Circulator run time after call for heat ends
Maximum Rate
WM97+70
WM97+110
WM97+155
RPM
RPM
RPM 1100
1400
1300 4300
5650
5500 4150
5450
5300
Boiler Model and altitude specific
(derated automatically if HIGH ALTITUDE is selected in
control setup)
NOTE: Adjusting boiler firing rate will affect AFUE rating.
Minimum Rate
WM97+70
WM97+110
WM97+155
RPM
RPM
RPM 1100
1400
1300 4300
5650
5500 1675
2150
2100
Boiler Model and altitude specific
(derated automatically if HIGH ALTITUDE is selected in
control setup)
NOTE: Adjusting boiler firing rate will affect AFUE rating.