Weil-McLain SlimFit 383-600-513 User manual

Series
Identification
Read the boiler rating label to determine the
series number. The rating label is located on
the top of the boiler (inside).
®
Part number 550-100-149/0420
Combustion Air Pressure Switch
Kit Instructions
Kit part number 383-600-513
SlimFit model numbers:
Left-hand boilers
(cleanout access on left side when facing burner end)
SF1000L — 1000 MBH input
SF1500L — 1500 MBH input
SF2000L — 2000 MBH input
Right-hand boilers
(cleanout access on right side when facing burner end)
SF1000R — 1000 MBH input
SF1500R — 1500 MBH input
SF2000R — 2000 MBH input
Recommended tools:
• 5/16” Nut driver
• Drill with 5/32” drill bit
• 13mm Wrench
• 7/16" Wrench
• read Sealant (pipe dope)
P/N 383-600-513 Kit contents
Item Description Part Number Qty
1
Combustion Air Pressure Switch 571-624-648 1
2 Screw Hex Washer Head Slotted 10/32 X 3/8 BP 562-135-710 2
3 Clip Plastic .25D Hole Snap-In 562-650-114 1
4 Combustion Air Pressure Switch Kit Instructions 550-100-149 1
5
1/8 inch Hose Barb Fitting 562-302-525 1
6
Harness - Air Pressure Switch 591-392-052 1
You must read and have the
SlimFit®Series 2 Boiler Manual
with you to proceed with these
instructions.
The Boiler Manual is available
online at Weil-McLain.com
This kit is intended to be installed on SlimFit 1000-2000 Series
2 boilers with vertical direct exhaust venting or direct vent with
sidewall air intake and vertical vent. See SlimFit Series 2 Boiler
Manual for specifi cs and other requirements for this venting
confi guration.
STOP!
Read before proceeding
Hazard definitions
The following defined terms are used throughout
this manual to bring attention to the presence
of hazards of various risk levels or to important
information concerning the life of the product.
Indicates presence of hazards that will
cause severe personal injury, death or
substantial property damage.
Indicates presence of hazards that can
cause severe personal injury, death or
substantial property damage.
Indicates presence of hazards that will
or can cause minor personal injury or
property damage.
Indicates special instructions on
installation, operation or maintenance
that are important but not related to
personal injury or property damage.
These instructions must only
be used by a qualified installer/
service technician. Read all
instructions completely before
beginning the installation. Failure to
follow all instructions can cause severe
personal injury, death or substantial
property damage.

SlimFit® Combustion air pressure switCh kit instruCtions
– 2 – Part number 550-100-149/0420
Clearance requirements
This procedure requires adequate clearance to remove the side
panels and center Weil-McLain post from the cleanout plate
side of the boiler.
It is assumed that the boiler will NOT need to be moved in order
to meet these clearance requirements.
Isolate the boiler
1. Disconnect power to boiler by Service Switch or On/Off
switch located on the top of the boiler, see Figure 1.
2. On the cleanout plate side of the boiler remove the two side
access panels, two (2) screws in bottom of Display panel,
Weil-Mclain center post, and piping end door for access to
internal components, see Figures 2 and 3.
STOP!
Read before proceeding
The boiler contains ceramic fiber and fiberglass
materials. Use care when handling these materials
per instructions in the Boiler Manual, available
on-line at Weil-McLain.com. Failure to comply
could result in severe personal injury.
Shut off power to the boiler and close main
gas valve. Close all isolation valves. Failure
to do so can result in severe personal injury, death
or substantial property damage.
Wait for the heat exchanger to cool down
before proceeding. Failure to do so can result
in severe personal injury.
Removing and reinstalling components can change
boiler behavior. After any maintenance procedure,
you must prove the boiler is operating correctly. To
do so, follow the complete procedure for boiler
and system start-up as instructed in the Boiler
Manual. Failure to comply could result in severe
personal injury, death or substantial property
damage.
For component location reference, see previous
pages. This is duplicated from the SlimFit Boiler
manual, but included here for convenience.
All instructions in the Boiler manual must be
followed, including fuel requirements, water
requirements and start-up/operation.
1 Electric entrance
2 Air pipe (air intake)
3 Vent pipe (vent connection)
4 Water outlet pipe
(system supply)
5 Water return pipe
(system return)
6 Gas connection
7 Condensate trap assembly
Figure 1 Typical boiler connections (all external components, wiring and piping shown for reference only)
BURNER END PIPING END
GAS CONNECTION SIDEGAS CONNECTION SIDE
Figure 2 Remove side access panels and display panel.

SlimFit® Combustion air pressure switCh instruCtions
– 3 –
Part number 550-100-149/0420
is recommended to use the actual bracket on the pressure
switch to mark the hole centers, then drill the marked holes.
6. With the two (2) screws provided, install the Combustion
Air Pressure Switch as shown in the image, see Figure 5,
(above). The pressure tap should be directed downward when
installed. Figure 5 shows installation on a "Left hand" boiler.
For "Right hand" boilers the pressure switch will have the
spade terminals facing the rear or water pipe end of the boiler.
7. Disconnect the white silicone pressure sense line from the
new Combustion Air Pressure Switch and route it through
the casting holes as shown in Figure 6.
8. Disconnect the white silicone sense line from the bottom of the
factory installedMinimum AirFlow Switchand connectit tothe
Y-fitting on the new Combustion Air Pressure Switch sense line.
(Figure 73 in boiler manual shows the Minimum Air Flow
Switch.)
9. Connect the short hose off of the Y-fitting back to the
Minimum Air Flow Switch.
10. Connect the long hose off of the Y-fitting on to the
Combustion Air Pressure Switch.
11. Disconnect the lower white with orange stripe wire from the
factory installed Minimum Air Flow Switch.
12. Using the P/N 591392052 wire harness provided in the kit,
connect the female terminal removed from the Minimum Air
Flow Switch to the male terminal end of the new harness. The
opposite end of that wire (female terminal) will be connected
3. Carefully remove the display panel that is still attached by
the communication harness. Place on top of boiler.
4. Locate the support frame bracket at the back of the boiler
(Water connection end). See Figure 4.
5. On the angled down face of the bracket locate two (2), 5/32”
holes, approximately 2” from the top of the bracket. If they
are not present, then the two (2) holes will have to be drilled
with a 5/32” drill bit approximately 2” from the top of the
bracket. The spacing of the two (2) holes should be 0.80”. It
Figure 4 Support frame bracket, shown with holes drilled
Figure 5 Pressure switch mounted to frame support bracketFigure 3 Remove center post.

SlimFit®Combustion air pressure switCh Kit instruCtions
Part number 550-100-149/0420
Start up, test and adjust boiler
1. Refer to Boiler Manual for proper startup procedure.
2. Follow all instructions in the Boiler Manual to start up, test
and adjust the boiler.
to the upper male terminal on the new Combustion Air
Pressure Switch.
13. The remaining wire from the P/N 591392052 harness with two
female terminals will connect to the lower male terminals on
the Combustion Air Pressure Switch and the factory installed
Minimum Air Flow Switch. When the installation is complete,
the Combustion Air Pressure Switch will be in series with
the original factory installed Minimum Air Pressure Switch.
(Figure 8)
14. Insert the plastic wire clip into the top frame as shown in
Figure 6.
15. Ensure wires going to the Combustion Air Pressure Switch
are routed through the plastic clip.
16. Using 13mm wrench, remove the 1/8 inch plug from the base
of the end casting at the water connection end of the boiler.
(Figure 7) Clean the internal threads to remove any debris.
17. Apply thread sealant (pipe dope) to the threaded end of the
1/8 inch hose barb supplied in the kit.
18. Using a 7/16" wrench, install the 1/8 inch hose barb fitting to
the open port in the end casting.
19. Connect the black-colored sense line from the Combustion
Air Pressure Switch to the hose barb fitting that was installed
to the end casting.
20. Restore the power to the boiler and proceed through the
Annual Start up / Safety checks identified in the SlimFit Series
2 Boiler Manual.
Reinstall the center post, display panels
and end and side access panels.
Reinstall the center post, end panel, side access panels and
display panel, by aligning top tabs with slots in the top jacket
frame, then sliding into slots in bottom frame until secure. (See
Figure 2, page 2)
Figure 7 Hose Barb Location
Figure 6 Pressure switch sense lines routing
Figure 8 Electrical Connections to Minimum Air Flow Switch