Weil-McLain 550 MBH Nstallation And Operation Manual page 52

®
SlimFit Series 3
Field wiring
1. Provides 120 VAC Dry Contact for boiler circulator.
2. Terminals are: 1 (H), 2 (H).
3. Maximum load: 10 amps (use relay if circulator load is higher).
4. Provide and install a fused disconnect or service switch (15-ampere rated
recommended) as required by applicable codes for circulator with maximum
load of 10 amps.
5. The boiler circulator is used in the boiler loop of the primary / secondary
piping. Primary / secondary piping is recommended to be used with the
SlimFit boiler to ensure proper flow through the heat exchanger.
1. Input 1 – Terminal Strip P11 – 4 & 5 (SlimFit control module).
2. Input 2 – Terminal Strip P15 – 1 & 2 (SlimFit control module).
3. Input 3 – Terminal Strip P15 – 3 & 4 (SlimFit control module).
4. These three inputs on each boiler can indicate a call for heat to the control
by means of a dry contact closure (thermostat, aquastat, or switch). (See
right and Figure 52, page 60).
5. The control provides inputs for up to three zones or three systems (priorities).
The control default setting is for three space heating zones tied to
PRIORITY 2, which is defaulted to FINNED TUBE BASEBOARD
system type.
6. For DHW applications, the aquastat can be connected to one of the three
input/output pairs. Take advantage of factory default settings by using PRI-
ORITY 1 for the DHW system. The default control setting for PRIORITY 1
is a direct-piped DHW system type.
7. The default control setting uses each input (INPUT 1, INPUT 2, and IN-
PUT 3) to control its respective 120VAC output (OUTPUT 1, OUTPUT 2,
and OUTPUT 3).
Use of 0–10VDC input for modulation disables Input 1 from creat-
ing calls for heat. See page 57 for instructions.
An input can be assigned to an AUX PUMP/OUTPUT function to
operate a system pump or interlock with a combustion air damper.
Inputs assigned for this function cannot be used for heat demand
operation. See page 75 and page 76 for more information on the
setup and selection of operating conditions.
circuits (Input1, Input2 and Input3 in Figure 52, page 60) or at-
tempt to supply 24 volts for any other application.
For thermostats that require a continuous 24-volt power source,
connect the common wire ("C") to
page 60). Do NOT exceed total amp draw per thermostat.
52
COMMERCIAL CONDENSING GAS
–
REQUIRED
(Expansion module, top right)
— supply 24-volt power to the thermostat
-
FIRED WATER BOILER
(continued)
relays to provide dry contacts to the Control ther-
mostat connections. The zone valve end switches
of 3-wire valves carry 24 VAC from the valve.
Pin 2 (see Figure 52,
—
Boiler Manual
See Figure 52, page 60 for details
–
As needed for systems
(SlimFit control module, left side)
See Figure 52, page 60 for details
— If using 3-wire zone valves, use
— 0.1 amps.
Part number 550-100-168/0516