Weil-McLain 2 Series Manual page 63

®
SlimFit Series 2
Control operation and setup
Control Priorities & Input/Outputs
For heating installations with multiple systems, the Control uses
PRIORITIES to determine the order of operation of the systems.
The control's MAX and MIN time settings determine the maximum
and minimum times a system will be operated before being turned
off to allow another system to operate. A typical example is DHW
priority — heat demand from the DHW system is given preference
over space heating, if set to use Priority 1.
Each PRIORITY has its own set of operating parameters. The control
prompts the user to select the system type (finned tube baseboard,
DHW, etc.) and is factory programmed with parameters suited to
each of these system types. The user can also choose CUSTOM to
create a system type.
The Control provides up to three priorities for single boiler applica-
tions and up to four priorities for network boiler applications. The
order of operation is: PRIORITY 1, PRIORITY 2, PRIORITY 3.
The 120VAC power output to the boiler circulator is provided by a
relay located on the boiler's Pump/Communications Board. For each
of the priorities, the control can be setup to run the boiler pump or to
leave it off. It is recommended to set Blr Circ to OFF for DHW that
is directly piped with its own DHW Circ.
Each boiler has three input/output pairs (INPUT/OUTPUT 1,
2 and 3. Control setup prompts the user to assign each of these I/O
pairs to a PRIORITY. The Control then knows which system (prior-
ity) to operate when the input receives a call for heat. On a call for heat
to an input, the Control closes the corresponding output (120VAC)
and begins controlling the boilers according to the setup for the as-
signed priority.
The MAX ON TIME setting controls the maximum time a priority will
be allowed to run before switching to a lower priority's call for heat.
The MIN ON TIME setting controls the minimum time a priority
will be operated before switching to a higher priority's call for heat,
or the next lower priority.
When multiple inputs are set up on the same priority, they will run at
the same time if the priority and inputs are active.
Control operation
The control responds to signals from:
Room thermostats.
DHW aquastats (if used).
Temperature sensors (boiler return, boiler supply, flue tempera-
ture) and, when used, system supply and system return, outdoor
temperature).
The control automatically adjusts blower speed (and gas flow rate) to
match boiler output to space heating and/or DHW heating demand.
The control provides three inputs and three outputs (for circulators
or auxiliary devices) plus a fourth boiler circulator output.
The outdoor temperature is used for supply temperature reset opera-
tion and for the warm weather shut down (WWSD) option.
System presets:
The Control provides presets by system type (see Fig-
ure 59, page 67 for complete list).
Part number 550-100-180/0917
COMMERCIAL CONDENSING GAS
- — Boiler Manual
FIRED WATER BOILER
(continued)
Setting Up the Boiler
Step 1
Step 2
Step 3
Step 4
Control WIZARD
The Wizard is available on initial setup of the boiler. It leads
through a step-by-step setup procedure designed for the ap-
plication chosen.
Context-sensitive help is available to explain the purpose of
key setup items.
Advanced settings for single boiler applications can be accessed
manually from the Contractor menu.
WIZARD Sequence
Boiler
Settings
Inputs/
Outputs
Set
Priorities
System
Settings
System
Types
Output
Activation
Priority
Switching
Date/Time
Information
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