Weil-McLain Series 4 User manual

Boiler Manual
!
WARNING
Installation and service of the boiler must be performed by a qualied installer or service technician.
Read all instructions, including this manual and all other information shipped with the boiler, before
installation or operation. Perform steps in the order given. Failure to comply could result in severe
personal injury, death or substantial property damage.
94
Steam Boiler - Series 4
For use with Gas, Light Oil, and Gas
with Light Oil Fired Burners
Manual Part Number 550-100-157/0523

2550-100-157/0523
 94  4 
Contents
Tools . . . . . . . . . . . . . . . . . . . . . . . . 4
Abbreviations . . . . . . . . . . . . . . . . . . . 4
- 
Safety Signals . . . . . . . . . . . . . . . . . . . 5
Please Read Before Proceeding . . . . . . . . . 5
Servicing a Boiler . . . . . . . . . . . . . . . . . . . . 5
Boiler Operation . . . . . . . . . . . . . . . . . . . . 6
Boiler Water. . . . . . . . . . . . . . . . . . . . . . . 6
Commonwealth of Massachusetts . . . . . . . . . . . 6
Freeze Protection Fluids . . . . . . . . . . . . . . . . 6
Damage from Water Contact . . . . . . . . . . . . . . 6
Frozen Water Damage . . . . . . . . . . . . . . . . . 6
- 
Prepare Boiler Location. . . . . . . . . . . . . . 7
Installation Compliance Requirements . . . . . . . . . 7
Checks Before Boiler Installation . . . . . . . . . . . . 7
Flooring and Foundation . . . . . . . . . . . . . . . . 8
Garage Installation . . . . . . . . . . . . . . . . . . . 8
Air Openings . . . . . . . . . . . . . . . . . . . . . . 8
Clearances . . . . . . . . . . . . . . . . . . . . . . . 9
Prepare the Boiler . . . . . . . . . . . . . . . . .10
Removing a Packaged Boiler from the Crate. . . . . 10
Removing a Preassembled Block from the Crate . . .11
Boiler Assembly . . . . . . . . . . . . . . . . . . 12
Assembling the Block. . . . . . . . . . . . . . . . . 12
Boiler Connections for Pressure Testing . . . . . . . 16
Perform Hydrostatic Pressure Test . . . . . . . . . . 16
Connect Steam Boiler Piping . . . . . . . . . . . . . 18
Steam Boiler Piping Guidelines. . . . . . . . . . . . 19
Burner Mounting Plate Installation . . . . . . . . . . 22
Front Observation Plate Installation . . . . . . . . . 22
Cleanout and Inspection Tappings . . . . . . . . . . 22
Jacket Installation Guidelines. . . . . . . . . . . . . 22
Jacket Parts Removal and Inspection . . . . . . . . 22
Preparing Jacket Panels for Use . . . . . . . . . . . 23
Installing Front and Rear Jacket Panels . . . . . . . 24
Install Side Panel Brackets and Splice Channels . . 24
Installing Side and Top Jacket Panels . . . . . . . . 24
Installing Front Cleanout Doors. . . . . . . . . . . . 26
Installing Front Cleanout Plates . . . . . . . . . . . 26
Installing the Flue Collar . . . . . . . . . . . . . . . 27
Installing the Back Access Door . . . . . . . . . . . 27
Tankless Heaters . . . . . . . . . . . . . . . . .28
Hot Water Precautions . . . . . . . . . . . . . . . . 28
Piping Tankless Heaters . . . . . . . . . . . . . . . 28
Steam Boiler Controls. . . . . . . . . . . . . . .29
Installing the Controls. . . . . . . . . . . . . . . . . 29
Ba󰀪e Assembly and Installation . . . . . . . . . .32
Boiler Ba󰀪e System . . . . . . . . . . . . . . . . . . . .32
Installing the 2nd Flue-Way Ba󰀪es . . . . . . . . . . . .33
Assembling the 3rd Flue-Way Ba󰀪es . . . . . . . . . . . 35
Installing the 3rd Flue-Way Ba󰀪es . . . . . . . . . . . . 37
Commonwealth of Massachusetts Installations. . 38
Venting and Combustion Air - General. . . . . .39
Code Compliance. . . . . . . . . . . . . . . . . . . 39
Combustion Air Contamination . . . . . . . . . . . . 39
Dual Fuel Venting Requirements . . . . . . . . . . . 39
Venting and Combustion Air Options . . . . .40
Existing Category I Vent System . . . . . . . . . . . 40
Test Procedure for Existing Vent System . . . . . . . 40
Room Air Openings . . . . . . . . . . . . . . . .41
Combustion Air Provision . . . . . . . . . . . . . . . 41
Sizing Combustion Air Openings . . . . . . . . . . . 41
Special Considerations . . . . . . . . . . . . . . . . 41
Breeching and Venting . . . . . . . . . . . . . .43
General Venting Information . . . . . . . . . . . . . 43
Construct Metal Breeching . . . . . . . . . . . . . . 43
Gas Venting Requirements — General. . . . . .44
General Gas Venting Information. . . . . . . . . . . 44
Engineered Vent System . . . . . . . . . . . . . . . 44
Types of Gas Venting Systems . . . . . . . . . . . . 45
Oil Venting Requirements. . . . . . . . . . . . .46
Using a Chimney . . . . . . . . . . . . . . . . . . . 46
Vent Piping Materials . . . . . . . . . . . . . . . . . 46
General Oil Venting Information . . . . . . . . . . . 47
Engineered Vent System . . . . . . . . . . . . . . . 47
Oil Venting System . . . . . . . . . . . . . . . . . . 48
Install Burner and Fill the System . . . . . . . . 49
Burner Installation . . . . . . . . . . . . . . . . . . 49
Wire the Burner and Boiler Controls . . . . . . . . . 49
Fill the Steam Boiler . . . . . . . . . . . . . . . . . 49
Fuel Piping . . . . . . . . . . . . . . . . . . . . . 50
Gas Piping . . . . . . . . . . . . . . . . . . . . . . 50
Fuel Oil Piping . . . . . . . . . . . . . . . . . . . . 50
Final Adjustments . . . . . . . . . . . . . . . . .51
Adjust the Burner and Damper Assembly . . . . . . 51
Skim Steam Boilers. . . . . . . . . . . . . . . . . . 52
Check the Boiler for Gas-Tight Seal . . . . . . . . . 52

3550-100-157/0523
94  4  
- 
Maintenance - General . . . . . . . . . . . . . .53
Handling Ceramic Fiber Materials . . . . . . . . . . 53
Perform Startup and Checkout . . . . . . . . . . . . 53
Annual Inspection . . . . . . . . . . . . . . . . .54
General Inspection Information . . . . . . . . . . . . 54
Inspect the Boiler Area . . . . . . . . . . . . . . . . 54
Inspect All Piping for Leaks . . . . . . . . . . . . . . 54
Inspect the Boiler Interior . . . . . . . . . . . . . . . . . . 54
Check Air Openings . . . . . . . . . . . . . . . . . 54
Boiler Service and Maintenance . . . . . . . . .55
Service and Maintenance Schedules. . . . . . . . . 55
Cleaning Heating Surfaces and Flue-ways . . . . . . 56
Cleaning the Water Side of the Boiler . . . . . . . . 56
Cleaning Float-Type Low Water Cut-o󰀨s . . . . . . . 56
Cleaning the Gauge Glass . . . . . . . . . . . . . . 57
Checking the Relief Valve . . . . . . . . . . . . . . 57
Troubleshooting — Priming or Foaming . . . . . . . 57
Seasonal Boiler Shutdown . . . . . . . . . . . . . . 58
Long-Term Boiler Shutdown . . . . . . . . . . . . . 58
- 
Miscellaneous Parts. . . . . . . . . . . . . . . .59
Ordering . . . . . . . . . . . . . . . . . . . . . .59
Replacement Parts . . . . . . . . . . . . . . . .60
Dimensions . . . . . . . . . . . . . . . . . . . .66
- 
Ratings . . . . . . . . . . . . . . . . . . . . . . .69
Maintenance Log . . . . . . . . . . . . . . . . .70
Installation and Service Certicate. . . . . . . . 71
Notes . . . . . . . . . . . . . . . . . . . . . . . . .71

4550-100-157/0523
 94  4 
Tools Needed Purpose
1/16" at blade screwdriver Wiring onto terminal blocks.
Phillips head screwdriver Jacket posts and channels
5/16" wrench or socket Sight glass and ba󰀪e assembly
11 mm wrench or socket Cover plate bolts
3/4" wrench or socket Burner mounting plate
15/16" wrench or socket Castings to castings tie rod nuts
1-1/16" wrench or socket Limit control
9/16" wrench Pressure and temperature gauge
Flat head screwdriver Sight glass
Pipe wrench Water piping and plugs
Multimeter Measurement readings on sensors
and electrical components
Manometer
(inclined or digital)
Measuring the gas pressure
coming to the boiler
Combustion analyzer
(digital preferred) Combustion testing
Contact thermometer Checking surface temperatures of
the heat exchanger and pipes
Abbreviation Description
AHRI Air-Conditioning, Heating, and
Refrigeration Institute
ANSI American National Standards Institute
ASME American Society of Mechanical Engineers
AWG American Wire Gauge
BTUH British Thermal Unit per Hour
CFM Cubic Feet Per Minute
CO Carbon Monoxide
CO2Carbon Dioxide
CP Consumer Protection
DHW Domestic Hot Water
HX Heat Exchanger
LWCO Low Water Cut-O󰀨
MAWP Maximum Allowable Working Pressure
MBH Thousands of Btuh
NFPA National Fire and Protection Agency
NIOSH National Institute for Occupational Safety
and Health
W.C. Water Column

Table 2 Common abbreviationsTable 1 Common tools needed
Tools

5550-100-157/0523
94  4  
1
2
3
4
5
6
7
8
This section is intended to provide safety information
for installers and users.
Section Contents
Safety Signals . . . . . . . . . . . . . . . . . . . . . 5
Please Read Before Proceeding . . . . . . . . . . . . 5

The following dened terms are used throughout this
manual to bring attention to the presence of hazards
or other important information.
DANGER
!
Danger indicates the presence of hazards that
will result in severe personal injury, death, or
substantial property damage.
!
WARNING
Warning indicates the presence of hazards that
can result in severe personal injury, death, or
substantial property damage.
CAUTION
!
Caution indicates the presence of hazards that
will or can result in minor personal injury or
property damage.
NOTICE
Notice indicates additional information that may be
related to property damage, but is not related to
personal injury.
IMPORTANT
Important indicates additional information that is
important, but is not related to personal injury or
property damage.

!
WARNING
Adhere to all following guidelines and
instructions in this section. Failure to adhere to
these guidelines can result in severe personal
injury, death, or substantial property damage.
Installer: Read all instructions, including this manual
and all other information shipped with the boiler,
before installation. Perform steps in the order given.
Consider piping and installation when determining
boiler location.
Write the Consumer Protection (CP) number and
serial number in the space provided on the Installation
and Service Certicate on page 71. The CP number
can be found on the boiler jacket.
Please include the boiler model number, CP
number, and serial number when calling or writing
about the boiler. The model number can be found on
the boiler rating label.
User: This manual is for use only by a qualied
heating installer or service technician. A qualied
service technician should inspect and service this
boiler at least once per year.
IMPORTANT
Any claims for damage or shortage in shipment
must be led immediately against the transportation
company by the consignee.
Servicing a Boiler
• To avoid electric shock, disconnect all electrical
supplies to the boiler before performing maintenance.
• To avoid a potential explosion, shut o󰀨 the fuel
supply to the boiler while servicing.
• To avoid severe burns, allow boiler to cool before
performing maintenance.
• This boiler contains ceramic ber and berglass
materials. Refer to the warning and instructions on
page 53.



6550-100-157/0523
 94  4 
1
2
3
4
5
6
7
8

Boiler Operation
• Do not block ow of combustion or ventilation air
to boiler.
• Should overheating occur, or gas supply fail to
shut o󰀨, do not turn o󰀨 or disconnect electrical
supply to pump. Shut o󰀨 the gas supply at a
location external to the appliance.
Boiler Water
• Since the heat exchanger is made of cast iron,
the water chemistry must be checked. The system
pH must be in the range of 7.0 to 8.5. Chemical
treatment may be required.
• Before connecting the boiler, thoroughly ush the
system to remove sediment. Install a strainer or other
sediment removal equipment if necessary. The cast
iron heat exchanger can be damaged by build-up or
corrosion due to sediment.
• Do not use petroleum-based cleaning or sealing
compounds in the boiler system. Gaskets and seals
in the system may be damaged, which can result in
substantial property damage.
• Continual fresh makeup water will reduce
boiler life. Mineral buildup in the heat exchanger
reduces heat transfer, overheats the cast iron heat
exchanger, and causes failure. Addition of oxygen
carried in by makeup water can cause internal
corrosion. Leaks in the boiler or piping must be
repaired at once to prevent makeup water. Use this
boiler ONLY in a closed-loop system.
• Do not add cold water to a hot boiler. Thermal
shock can cause the heat exchanger to crack.
Commonwealth of Massachusetts
When the boiler is installed within the Commonwealth
of Massachusetts:
• This product must be installed by a licensed
plumber or gas tter.
• If antifreeze is used, a reduced pressure back-ow
preventer device shall be used.
See page 38 for sidewall vent air installations.
Freeze Protection Fluids
NEVER use automotive or standard glycol antifreeze.
Use antifreeze specically made for hydronic
systems; inhibited propylene glycol is recommended.
Thoroughly clean and ush any replacement boiler
system that has used glycol before installing the new
94 boiler.
Damage from Water Contact
DANGER
!
DO NOT attempt to operate any boiler if any
part of the boiler, burner, or controls has been
partially or fully sprayed with or submerged
under water. The boiler must either be replaced
or completely repaired and inspected. The boiler
and all components must be in good condition
and fully reliable before operation.
If these requirements are not met, operating
the boiler will cause re, explosion, and electrical
shock hazards, leading to serious injury, death,
or substantial property damage.
Saltwater damage: The immediate e󰀨ects of
saltwater damage are like those of freshwater,
with electrical components shorting out and the
removal of critical lubricants. However, salt and other
contaminants left behind can lead to long term issues
due to the conductive and corrosive nature of salt
residue. WM Technologies equipment contaminated
with saltwater or polluted water will no longer be
covered under warranty and should be replaced.
Electrical damage: If any electrical component or
wiring has, or is suspected to have come into contact
with water, replace the boiler.
Frozen Water Damage
Power outages, unattended residences or buildings,
boiler component failures, or other electrical system
failures in cold weather could result in frozen plumbing
and water damage in a matter of hours. Consult with
a boiler contractor or a home security agent to take
preventative actions, such as installing a security
system that operates during power outages, senses
low temperature, and initiates an e󰀨ective action.

7550-100-157/0523
94  4  
1
2
3
4
5
6
7
8
This section is intended to provide installation
instructions for qualied heating installers.
Section Contents
Prepare Boiler Location. . . . . . . . . . . . . . . . . 7
Prepare the Boiler . . . . . . . . . . . . . . . . . . 10
Boiler Assembly. . . . . . . . . . . . . . . . . . . . 12
Tankless Heaters . . . . . . . . . . . . . . . . . . . 28
Steam Boiler Controls . . . . . . . . . . . . . .29
Baffle Assembly and Installation . . . . . . . . .32
Commonwealth of Massachusetts Installations . .38
Venting and Combustion Air - General . . . . . . . . . . . .39
Venting and Combustion Air Options . . . . . . . . . 40
Room Air Openings . . . . . . . . . . . . . . . . . . 41
Breeching and Venting . . . . . . . . . . . . . . . . 43
Gas Venting Requirements — General. . . . . . . . 44
Oil Venting Requirements . . . . . . . . . . . . . . 46
Install Burner and Fill the System . . . . . . . . . . 49
Fuel Piping . . . . . . . . . . . . . . . . . . . . . . 50
Final Adjustments. . . . . . . . . . . . . . . . . . . 51

Installation Compliance Requirements
• Local, state, provincial, and national codes, laws,
regulations, and ordinances.
• National Fuel Gas Code – ANSI Z223.1/NFPA 54,
latest edition.
• Chimneys, Fireplaces, Vents, and Solid Fuel
Burning Appliances – ANSI/NFPA 211, latest
edition.
• Installation of Oil Burning Equipment – ANSI/NFPA
31, latest edition.
• National Electrical Code – ANSI/NFPA 70, latest
edition.
• Where required by the authority having
jurisdiction, the installation must conform to the
Standard for Controls and Safety Devices for
Automatically Fired Boilers – ANSI/ASME CSD-1,
latest edition.
IMPORTANT
The 94 Series 4 steam boiler met safe lighting and
other performance criteria when the boiler underwent
tests specied in UL 726 & UL 795, latest editions.
Checks Before Boiler Installation
1. Check for nearby connections to:
• System water piping
• Venting systems
• Fuel supply
• Electrical Power
• Combustion and ventilation air supply
2. Check area around boiler. Remove any
combustible materials, gasoline, and other
ammable liquids and vapors.
!
WARNING
Failure to keep boiler area clear and free of
combustible materials, gasoline, and other
ammable liquids and vapors can create an
explosion hazard, which can result in severe
personal injury, death, or substantial property
damage.
3. Check the boiler location to ensure it protects the
gas control system components from dripping
or spraying water and rain during operation or
service.
4. If a new boiler is replacing the existing boiler,
check for and correct system problems:
• System leaks causing oxygen corrosion or heat
exchanger cracks from hard water deposits.
• Incorrect expansion tank sizing.
• Lack of freeze protection in boiler water.



8550-100-157/0523
 94  4 
1
2
3
4
5
6
7
8
Flooring and Foundation
The 94 boiler is approved for installation on
combustible ooring, but must never be installed on
carpeting.
!
WARNING
Do not install the boiler on carpeting even if
a foundation is used. Installing a boiler on
carpeting can cause a re, which can result in
severe personal injury, death, or substantial
property damage.
1. The boiler mounting surface must be level and
suitable for the load.
2. Provide a solid foundation pad at least 4.0"
(101.6 mm) above the oor if any of the following
is true:
• Floor can become ooded.
• The oor is dirt, sand, gravel, or other loose
material.
• The boiler mounting area is severely uneven or
sloped.
3. Foundation may be brick or concrete
construction. The minimum foundation
dimensions are listed in Table 3.
4. If ooding is possible, elevate the boiler
su󰀩ciently to prevent water from reaching the
boiler.
Garage Installation
Take the following special precautions when installing
the boiler in a garage.
• Mount the boiler at a height above the oor as
specied in the latest edition of the National Fuel
Gas Code – ANSI Z223.1/NFPA 54, latest edition,
for U.S. installations.
• Locate or protect the boiler so it cannot be
damaged by a moving vehicle.
• Ensure that the installation complies with all
applicable codes.
Air Openings
Openings in oors, walls, ceilings, or roofs must be
designed for re stopping as required by local codes.
Vent pipe openings through combustible materials
must be 3/8" (9.5 mm) larger in diameter than the
vent pipe.
Air pipe openings should be 3/8" (9.5 mm) larger
in diameter than the pipe or as required by the pipe
manufacturer.
!
WARNING
Pipe openings that do not have the required
diameter can cause a re, which can result in
severe personal injury, death, or substantial
property damage.
Provide air openings for combustion air and
ventilation of the room. Follow the National Fuel Gas
Code – ANSI Z223.1/NFPA 54, latest edition for the
U.S.
Follow all applicable codes to size and verify
size of the combustion and ventilation air openings
into the space. See the Venting and Combustion
Air sections starting on page 39 for required air
openings and sizing.

Table 3 Minimum foundation dimensions
Boiler
Model
Length, L1
(inches)
Height, H
(All)
Boiler
Model
Length, L1
(inches)
1494 91
Consult burner
manufacturer
for required
clearances.
2094 127
1594 97 2194 133
1694 103 2294 139
1794 109 2394 145
1894 115 2494 151
1994 121 2594 157
Figure 1 Boiler foundation, when required
230032
H
H
66”
L1
L1
(2) ¼” x 3”
Steel plates x L1 long
x 51” apart
4”
51”
Back of boiler
Back of boiler
Always use steel strips as
shown for proper draw-up
and alignment of sections.

9550-100-157/0523
94  4  
1
2
3
4
5
6
7
8
Clearances
There are minimum clearance requirements for
the boiler from combustible surfaces. There are
recommended service access clearances. See
Figure 2 for all clearances.
IMPORTANT
Without the recommended minimum clearances for
service access, it may not be possible to service the
boiler without removing it from the space.
230033
Top
Top
Right
Side
Right
Side
Edge of opening within 12 inches of floor.
Edge of opening within 12 inches of floor.
Air openings
(when required)
Air openings
(when required)
Controls end
Front
Controls end
Front
Left
Side
Left
Side
Edge of opening within 12 inches of ceiling.
Edge of opening within 12 inches of ceiling.
Rear
Rear
Ensure that the installation complies with all state, local, and applicable codes.
Clearance from:
Minimum clearances to
combustible surfaces
(inches)
Minimum allowable
service clearances
(inches)
Recommended minimum service
access clearances
(inches)
Controls end (Front) 48 48 48
Right side 6 44 44
(clean and remove tankless heater)
Left side 6 6 6
Flue 9 9 9*
Rear 9 50 50 (breeching)*
Top 24 24 24
Floor 0 0 0
Single-wall vent pipe 18 18 18
Double-wall vent pipe Refer to vent pipe manufacturer's recommendations for vent pipe clearances.
Note: Allow su󰀩cient space for cleaning, servicing, and installing the burner. See burner literature for length and recommended
service clearances.
*Flue pipe and breeching clearances take precedence over jacket clearances.
Figure 2 Clearances for 88 Boilers

10 550-100-157/0523
 94  4 
1
2
3
4
5
6
7
8

Removing a Packaged Boiler from the Crate
Leave the boiler in the crate pallet until ready to place
in the nal location. Follow all removal instructions.
IMPORTANT
Cables used for lifting are not provided by Weil-McLain.
!
WARNING
Ensure the equipment and cables used for lifting
are designed to handle the load. See Table 4
for approximate weights of section assemblies.
Failure to comply can result in severe personal
injury, death or substantial property damage.
1. Move the crate to a solid, level surface. The crate
must be sitting securely on the ground.
2. Remove the top jacket panels and set aside until
after piping installation.
3. Remove four lag screws from the shipping brackets.
4. Remove the boiler from the skid with a crane or a
hoist. See Table 4 for lifting weight.
• Crane: Hook middle of each cable to the eye of
the crane.
• Hoist: Hook middle of each cable to the hoist.
Raise boiler o󰀨 skid. Use pipe rollers under skid
angles to roll the boiler.
5. Place 1/4" x 3" steel plates on the oor or
foundation. Space them 51" apart as shown in
Figure 1, page 8.
6. Place the boiler in the nal position. If using a
foundation, center the boiler on the foundation.
7. Level the boiler. Shim under legs if necessary.
8. Cut o󰀨 the cables.
!
WARNING
Cables are not intended for long-term use.
Cables may corrode inside the boiler, weakening
their lifting strength. Failure to remove cables
can result in severe personal injury, death, or
substantial property damage.
9. Inspect the block assembly for disjointed
sections.
10. Check the gas-tight seal of the ue collector hood
and clean out plates.
a. Check inside the section assembly for any light
passing through unsealed areas.
b. Mark all unsealed areas and check for the
following:
• Damaged gaskets.
• Displaced sealing rope.
• Loose bolts or nuts.
c. Correct all conditions and repeat the previous
steps. If unsealed areas still exist, contact Tech
Services before continuing with installation.
11. Proceed to page 16 and perform pressure
testing.
Boiler Model
Number
Approximate
Lifting Weight
(lbs.)
Minimum Sling
Length
(Crane Hook to
Boiler Lifting Lugs)
1494 13700 5' 0"
1594 14500 5' 0"
1694 15400 5' 0"
1794 16200 5' 0"
1894 17100 5' 0"
1994 17900 5' 6"
2094 18700 5' 6"
2194 19800 7' 6"
2294 20600 7' 6"
2394 21500 7' 6"
2494 22400 8' 0"
2594 23200 8' 0"
Table 4 Section assembly lifting weights

11550-100-157/0523
94  4  
1
2
3
4
5
6
7
8
Leave the block assembly in the crate pallet until
ready to place in the nal location. Follow all removal
instructions.
IMPORTANT
Cables used for lifting are not provided by Weil-McLain.
!
WARNING
Ensure the equipment and cables used for lifting
are designed to handle the load. See Table 4,
page 10 for approximate weights of section
assemblies. Failure to comply can result in
severe personal injury, death or substantial
property damage.
1. Move the crate to a solid, level surface. The crate
must be sitting securely on the ground.
2. Remove four lag screws from the shipping brackets.
3. Remove the block assembly from the skid with a
crane or a hoist. See Table 4, page 10 for lifting
weight.
• Crane: Attach free end of cables to the eye of
the crane.
• Hoist: Attach free end of cables to the hoist.
Raise the block o󰀨 the skid. Use pipe rollers
under skid angles to roll the block.
4. Place 1/4" x 3" steel plates on the oor or
foundation. Space them 51" apart as shown in
Figure 1, page 8.
5. Place the boiler in the nal position. If using a
foundation, center the boiler on the foundation.
6. Level the boiler. Shim under legs if necessary.
7. Cut o󰀨 the cables.
!
WARNING
Cables are not intended for long-term use.
Cables may corrode inside the boiler, weakening
their lifting strength. Failure to remove cables
can result in severe personal injury, death, or
substantial property damage.
8. Inspect the block assembly for disjointed
sections.
9. Check the gas-tight seal of the ue collector hood
and clean out plates.
a. Check inside the section assembly for any light
passing through unsealed areas.
b. Mark all unsealed areas and check for the
following:
• Damaged gaskets.
• Displaced sealing rope.
• Loose bolts or nuts.
c. Correct all conditions and repeat the previous
steps. If unsealed areas still exist, contact Tech
Services before continuing with installation.
!
WARNING
Gas-tight seal must be maintained to prevent
possible ue gas leakage and carbon monoxide
emissions. Leakage and emissions can result in
severe personal injury or death.
10. Proceed to page 16 and perform pressure
testing.
Removing a Preassembled Block from the Crate

12 550-100-157/0523
 94  4 
1
2
3
4
5
6
7
8

Assembling the Block
!
WARNING
Ensure sections are supported. Sections are top-
heavy. Unbolted sections may fall if not supported,
which can result in severe personal injury or death.
NOTICE
Machined port surfaces must remain clear of any
adhesive properties. Adhesive in the seal pocket
can damage the seal, which can result in substantial
boiler and other property damage.
Prepare and position the back section:
1. Place 1/4" x 3" steel plates on the oor or foundation,
spaced 51"apart. See Figure 1, page 8.
2. Apply 1/8" continuous bead of sealing rope
adhesive in sealing rope grooves around section
perimeter and ue-ways. See Figure 3 and Figure 4.
3. The boiler is supplied with two types of section
sealing rope: uncoated rope, and coated rope
with a narrow uncoated strip. Place the 5/8" rope
in the rope grooves:
a. Use the uncoated rope only on the ue-ways
as shown in Figure 4.
b. Use the coated rope around the perimeter
and around the upper nipple port as shown in
Figure 4. The uncoated side of the rope must
be pressed into the adhesive as shown in
order to obtain a proper adhesion.
c. Use one continuous piece of the coated rope
around the entire outside groove of the casting.
Connect the coated rope at one of the top sides.
Do not meet the two ends of the coated rope
between the nipple port and ue-way area.
d. Apply additional sealing rope adhesive where
the two ends of the coated rope meet. This will
ensure a leak-free joint.
4. Around curves, grasp rope at 1" intervals and
push together. Do not stretch the rope.
5. Cut the rope as each section is completed.
!
WARNING
Do not pre-cut rope. Gas-tight seal must be
maintained to prevent possible ue gas leakage
and carbon monoxide emissions. Failure to comply
can result in severe personal injury or death.
1/8-inch
bead of
adhesive
230037
Figure 3 Sealing rope adhesive
Figure 4 Sealing rope placement
UNCOATED rope
(around flueways)
6” elastomer
sealing rings
COATED rope —
around perimeter
and nipple port as
shown – place
with uncoated
strip facing down,
pressed into the
adhesive
Cut the UNCOATED
rope diagonally at
points where the
uncoated and coated
rope meet.
Adhesive in
rope groove
Place uncoated
strip on coated
rope against the
adhesive
9” elastomer
sealing ring
Coated rope
230038
T
OP VIEW
Connect the coated
rope ends at the top
on either side of the
casting.
DO NOT connect in
the middle.

13550-100-157/0523
94  4  
1
2
3
4
5
6
7
8
Assembling the Block, continued
NOTICE
Do not use petroleum based cleaning or sealing
compounds in the boiler system; usage can result in
severe boiler damage and substantial property damage.
6. Remove any grit from port machined surfaces
with a clean rag.
7. Place 9" and 6" sealing rings in appropriate port
openings as shown in Figure 4, page 12. If
sealing ring slips out of groove, stretch ring gently
and reposition in groove.
8. Apply a continuous bead of silicone sealant no
larger than 1/16" around entire outside edge of
outer machined surface of port. Refer to Figure 5.
Do not apply silicone sealant on, next to, or under
the sealing ring.
NOTICE
Apply silicone sealant as specied to prevent
unburned oil vapors from coming in contact with the
sealing ring. Failure to comply can result in severe
boiler damage and substantial property damage.
9. Hoist the back section upright.
10. Move the rear section into position on the steel
rails.
a. If using a foundation, the section should be
4" from the end of the foundation as shown in
Figure 1, page 8.
11. Block under the ue-way outlet to hold the rear
section upright in plumb position.
CAUTION
!
The back section must be plumb before installing
other sections to ensure correct block assembly.
12. The block can be removed after several sections
have been installed and the assembly is stable.
(continued on the next page)
g
i
n
r
g
n
li
a
e
S
g
i
n
r
g
n
li
a
e
S
Silicone sealant
(apply per instructions)
Silicone sealant
(apply per instructions)
230039
Figure 5 Silicone sealant

14 550-100-157/0523
 94  4 
1
2
3
4
5
6
7
8
Assembling the Block, continued
Install the intermediate sections:
1. Remove and discard 3/8" diameter shipping tie
rods.
2. Remove grit from port machined surfaces with
clean rag.
3. Remove grit from tapped holes in all sections.
4. Position the intermediate section so aligning lugs
t into sockets of next section. See Figure 6.
IMPORTANT
Install tankless intermediate (TI) and supply
intermediate sections (when used) in the order shown
in Table 5, page 15.
5. Draw the sections together until metal-to-metal
contact is made around machined port openings
as shown in Figure 6.
a. Oil the threads on four draw rods. Install a
washer and nut on the end to be tightened.
Use only a nut on the other end.
b. Uniformly draw the sections together, starting
at the end with the washer and nut.
IMPORTANT
Leave an equal amount of thread on each end of
the draw rod; this is needed to allow securing the
jacket support brackets in place. To avoid jacket
interference, the draw rods must not extend past the
face of the front or back sections.
c. Draw rods should be torqued to a range of 100
to 120 ft-lbs. Do not back o󰀨 draw rods.
d. Metal-to-metal contact will be achieved around
port openings. See Figure 6. If gap occurs, it
should be no greater than .032". Check with a
feeler gauge.
e. If the gap around the machined port opening
exceeds .032", check for rope extending
from rope grooves, dirt on port openings or
sockets, or misaligned lugs. If corrections are
made and a gap still exists, contact your WM
Technologies distributor before continuing
installation.
NOTICE
After erecting the rst intermediate section, check
both sections for plumb. Failure to plumb sections
can cause misaligned piping and breeching, which
can result in property damage.
!
WARNING
A gas-tight seal prevents possible ue gas
leakage and carbon monoxide emission. Failure
to position sealing rope properly can prevent
a gas-tight seal, which can result in severe
personal injury or death.
6. Check each section for proper sealing rope
position before proceeding to the next section.
7. Install remaining intermediate sections and front
section using the same procedure in this section.
If using tankless heater (TI) sections:
• Install tankless heaters and gaskets or heater
cover plates and gaskets. Use 3/8" x 3/4" studs,
washers, and nuts.

Section
Section
Elastomer
sealing ring
Metal-
to-metal
contact
230040
Silicone
sealant
Figure 6 Sealing ring installation and port alignment

15550-100-157/0523
94  4  
1
2
3
4
5
6
7
8
Table 5 Section arrangement
Steam
Boiler
Models
Placement of special intermediate sections (TI and SI)
Numbering from REAR to FRONT, beginning with rear section as section number 1
TI sections with tankless coil openings
(number of coils) SI sections
with supply
tappings
1 2 3 4 5 6 7 8
1494 S 6 4, 6 2, 4, 6 4, 6, 11, 13 2, 4, 6, 11, 13 2, 4, 6, 9, 11, 13 — — —
1594 S 6 4, 6 2, 4, 6 4, 6, 12, 14 2, 4, 6, 12, 14 2, 4, 6, 10, 12, 14 — — —
1694 S 6 4, 6 2, 4, 6 4, 6, 13, 15 2, 4, 6, 13, 15 2, 4, 6, 9, 11, 13 2, 4, 6, 9, 11, 13, 15 — —
1794 S 7 5, 7 3, 5, 7 5, 7, 14, 16 3, 5, 7, 14, 16 3, 5, 7, 10, 12, 14 3, 5, 7, 10, 12, 14, 16 — —
1894 S 8 6, 8 2, 4, 6 2, 4, 6, 8 2, 4, 6, 8, 15 2, 4, 6, 8, 15, 17 2, 4, 6, 8, 11, 13, 15 2, 4, 6, 8, 11, 13, 15, 17 —
1994 S 6 4, 6 2, 4, 6 4, 6, 9, 11 2, 4, 6, 9, 11 2, 4, 6, 9, 11, 16 2, 4, 6, 9, 11, 16, 18 2, 4, 6, 9, 11, 14, 16, 18 —
2094 S 6 4, 6 2, 4, 6 4, 6, 10, 12 2, 4, 6, 10, 12 2, 4, 6, 10, 12, 17 2, 4, 6, 10, 12, 17, 19 2, 4, 6, 10, 12, 15, 17, 19 —
2194 S 2 2, 9 2, 9, 11 2, 9, 11, 13 2, 9, 11, 13, 20 — — — 4, 6, 16, 18
2294 S 2 2, 10 2, 10, 12 2, 10, 12, 14 2, 10, 12, 14, 21 — — — 4, 6, 17, 19
2394 S 2 2, 9 2, 9, 11 2, 9, 11, 13 2, 9, 11, 13, 15 2, 9, 11, 13, 15, 22 — — 4, 6, 18, 20
2494 S 8 2, 8 2, 8, 12 2, 8, 12, 14 2, 8, 12, 14, 16 2, 8, 12, 14, 16, 23 — — 4, 6, 19, 21
2594 S 8 2, 8 2, 8, 11 2, 8, 11, 13 2, 8, 11, 13, 15 2, 8, 11, 13, 15, 17 2, 8, 11, 13, 15, 17, 24 —4, 6, 20, 22
If the boiler was ordered with tankless coils, the heaters must be located on the right-hand side of the boiler. It is important to position the TI sections
(where used) in the exact location in the boiler section assembly as shown above so the heater knockout openings in the jacket side panels will
accommodate the heaters. If the TI sections and internal water heaters are not positioned in the boiler section assembly as shown above, the installer
must cut openings in the jacket side panels to accommodate the heaters.
TI = Tankless Intermediate section
SI = Supply Intermediate section

16 550-100-157/0523
 94  4 
1
2
3
4
5
6
7
8

Boiler Connections for Pressure Testing
Install the boiler connections per the appropriate
instructions below according to the boiler model.
Models 1494-2094:
1. Secure supply elbows and outlet gaskets to front
and back sections.
a. Use 5/8" x 3" studs, nuts, and washers.
b. Thread the at end of the studs into the
sections.
2. Secure 6" NPT return opening counter ange and
gasket to back section. Use 3/4" x 2" cap screws
and washers.
Models 2194-2594:
1. Secure outlet cover plates and gaskets to front
and back sections.
a. The 3/4" tappings in plates should be at top.
b. Use 5/8" x 1-3/4" bolts.
2. Secure 10" supply outlets and gaskets on top of
"SI" sections, when used.
a. Supply outlet installed close to boiler front
should have 1-1/4" tapping facing front.
b. Use 5/8" x 3" studs, nuts, and washers.
3. Secure 6" NPT return opening counter ange and
gasket to back section using 3/4" x 2" hex head
cap screws and washers.
Perform Hydrostatic Pressure Test
1. See Figure 7, page 17 for tapping locations.
2. Install a water pressure gauge for testing only.
a. The pressure gauge must be able to handle
the required test pressure stated in this
section. Gauge maximum should be at least
1.5 times the test pressure.
b. Install the pressure test gauge in the tapping
specied in Figure 7, page 17.
3. Install an air vent in an upper tapping.
4. Install 3" close nipples and caps in washout
tappings on the front section.
5. Prepare the rear section.
a. Install a drain valve (furnished by installer) in
one of the washout tappings on the rear section.
b. Verify drain valve size per Figure 7, page 17.
c. Install a 2" x 2-1/2" nipple and cap in the other
washout tapping.
6. Plug or use blind anges on remaining tappings.
NOTICE
Do not pressure test with any control installed.
Damage to control can occur due to overpressure.
7. Fill the boiler with water. Vent all air.
8. Pressure test the boiler for at least 10 minutes at
a pressure between 45 and 55 psig.
NOTICE
Do not exceed above test pressures by more than 10
psig.
!
WARNING
Do not leave boiler unattended. Cold water ll
could expand and cause excessive pressure,
which can result in severe personal injury, death
or substantial property damage.
9. Check for maintained gauge pressure and leaks.
Repair any leaks immediately.
NOTICE
Leaks must be repaired at once. Failure to do so
can damage boiler, resulting in substantial property
damage.
NOTICE
Do not use petroleum-based cleaning or sealing
compounds in boiler system. Using these compounds
can cause severe damage to system components,
resulting in substantial property damage.
10. Drain the boiler. Remove the air vent, boiler drain,
and pressure gauge.
11. Remove plugs from tappings that will be used for
controls and accessories.

17550-100-157/0523
94  4  
1
2
3
4
5
6
7
8
Figure 7 Model 94 steam boiler control tappings
M3
J1
Y1
Y2
J2
J5
M4
Upper
left
front
M1
M2
Upper
right
front
Front supply elbow
1494 – 2094
Front supply elbow
1494 – 2094
STEAM
FRONT
STEAM
FRONT
X1
X2
10” FLG (2194–2594)
W1
V1 Cover plate
W2
P1
T1
S1
8” FLG (1494–2094)
Left side
Top front supply
2194 – 2594
Top front supply
2194 – 2594
T2
R1
Right side
S1
Z1 Z2
STEAM
REAR
STEAM
REAR
Rear supply elbow
1494 – 2094
6” NPT Return
Top rear supply
2194 – 2594
W3
V2 Cover plate
W4
X3
X4
10” FLG (2194–2594)
P2
T3
8” FLG (1494–2094)
Left side
T4
R2
Right side
S2
S2
Z3 Z4
230041
Location Size Function
J1 1/2 Pressure test gauge — REMOVE
AFTER HYDROSTATIC TEST
J1 + J5 1/2 Gauge glass
J2 1/2 PLUG this tapping — not used
M3 1 PLUG this tapping — not used
M1 + M2
1
Float-type low water cuto󰀨, LWCO/
pump control, or LWCO/feeder
combination.
M3 + M4
P1 3 Skim tapping
P2 3 Steam pressure relief valve
R1 4 Skim tapping
R2 4 Steam pressure relief valve
S1 3/4 Steam pressure gauge – or –
Pressure controls (limit, operating, etc.)
S2 3/4 Pressure controls (limit, operating, etc.)
T1 or T2 1-1/4 Pressure controls (limit, operating, etc.)
T3 or T4 1-1/4 Steam pressure gauge – or –
Pressure controls (limit, operating, etc.)
V1 or V2 4Steam pressure relief valve – or –
Skim tapping
W1 or W2 3/4 Steam pressure gauge – or –
Pressure controls (limit, operating, etc.)
W3 or W4 3/4 Pressure controls (limit, operating, etc.)
X1 & X2 1-1/4 PLUG these tappings — not used
X3 & X4 1-1/4 PLUG these tappings — not used
Y1 & Y2 3/8 Try cocks
Z1 or Z2 2
Cleanout tappings, front section. Install
2" NPT close nipple and 2" NPT cap in
each cleanout tapping.
Z3 or Z4 2
Cleanout or drain tappings, rear
section. Install drain valve in one
tapping, and 2" NPT x 2-1/2" length
nipple and 2" NPT cap in the other
tapping.
——
Low limit temperature control (when
using tankless heaters). Locate in
control tapping on one of the tankless
heaters.
IMPORTANT
Controls and ttings must not obstruct cleanout openings or
prevent required access to the boiler or components.
Boiler model Minimum drain/
blow-o󰀨 valve size
1494-2194 1-1/4"
2294-2594 2"

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
Connect Steam Boiler Piping
1. Hartford loop piping arrangement and wet return are
required for steam boilers. Use the Hartford loop for
both pumped-return and gravity-return systems.
2. Maintain a 24" minimum from waterline to bottom
of header (86-3/4" from bottom of section).
3. When using a condensate receiver, feed pump must
be energized by a boiler-mounted pump controller.
4. Install piping as shown on pages 19-20
for single boilers. See page 21 for additional
requirements when piping multiple boilers.
5. Size return pipe as follows.
a. Pumped return — Size return piping by pump.
b. Gravity return — Size gravity return same as
Hartford loop equalizer pipe size.
6. Install system drain valve in lowest part of return
piping close to boiler. See Figure 7, page 17 for
sizing.
7. Connect cold water ll piping as shown in Figure 8.
Recommended valves and water meter are also
shown, if used. Water meter will detect added
makeup water, indicating leaks in the system.
8. Condensate return piping:
a. Satisfactory operation of any steam heating
system depends on an adequate return of
condensate to maintain a steady water level.
b. Avoid adding excessive amounts of raw
makeup water.
c. Where condensate return is not adequate, a
low water cuto󰀨 with pump control, condensate
receiver, and condensate boiler feed pump
should be installed.
d. See Figure 9 for piping and Table 6 for sizing.
Boiler
Model Number
AHRI Gross Output
(lbs steam per hour)
Gallons
Condensate per
hour
Minimum Condensate Receiver Capacity (gallons)* Recommended
condensate feed
pump capacity
GPM at 15 PSI
15-minute boiler
operation
30-minute boiler
operation
45-minute boiler
operation
60-minute boiler
operation
1494 3868 464 136 272 408 544 15.0
1594 4165 500 147 294 441 588 16.5
1694 4463 536 158 316 474 632 17.5
1794 4760 571 168 336 504 672 19.0
1894 5058 607 179 358 537 716 20.0
1994 5355 643 189 378 567 756 21.0
2094 5653 678 199 398 597 796 22 0
2194 5950 714 210 420 630 840 22.0
2294 6307 757 220 440 660 880 24.0
2394 6545 785 231 462 693 924 26.0
2494 6902 828 241 482 723 964 27.0
2594 7140 857 252 504 756 1,008 28.0
*Maximum time to when condensate returns to the boiler — the longer the time for condensate to return, the larger the receiver must be.
Figure 8 Cold water ll piping Figure 9 Condensate piping to boiler
Table 6 Condensate receiver capacity requirements
Cold
water
fill
Manual
isolation
valve
Manual
isolation
valve
Pressure
reducing
valve
(when used)
Check
valve
Water
meter
T
o condensate return
piping or condensate
receiver
230047
Vent to atmosphere
System condensate return
To boiler
condensate return
Manual isolation valve
Manual isolation valve
Check valve
Strainer
Feed pump
Cold water fill piping 230048

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1
2
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5
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8
Steam Boiler Piping Guidelines
Piping system must be installed as shown, using
pipe sizes shown. Pipe sizes shown are for two-pipe,
pumped-return systems. Adjust pipe sizing as needed
when connecting to gravity-return systems. Consult
a local Weil-McLain distributor or sales o󰀩ce before
installing alternate piping.
NOTICE
Install piping as shown. Improperly piped systems
or undersized piping can contribute to erratic boiler
operation and possible boiler or system damage.
NOTICE
The boiler header must always be at least 24" above
the water line, as shown in all steam boiler piping
diagrams. Installing the pipe lower will result in
increased water carryover to the system, which can
result in serious damage to system components and
oxygen corrosion due to excess makeup water.
Hartford loop piping for all steam boilers:
1. Install the system supply pipe between the
equalizer elbow and the last boiler riser pipe
connection to the header; this assists in
separating water from the steam as it turns
upward into the steam supply pipe.
2. Locate the top of the Hartford loop return nipple
at least 4" below the water line, as shown.
(continued on the next page)
Figure 10 Models 1494-2094 steam piping – two 8" risers required
Back
of
boiler
Back
of
boiler
62¾”
62¾”
24” min
24” min
4”
4”
230049
Water line
Water line
Equalizer J
Equalizer J
Header H
Header H
Riser A
Riser A
BOILER
RETURN
10
9
8
7
11
6
5
4
1
3
2
Pipe Dimensions
Model Riser A Riser B Header H Equalizer J
1494-1594 8" 8" 8" 4"
1694-2094 8" 8" 10" 4"
Legend – Figure 10
1. Riser pipes (one for each supply outlet)
2. Horizontal pipes needed to o󰀨set the header to
allow for expansion and contraction of the header
3. Steam supply must be located between last riser
connection and equalizer elbow
4. Equalizer elbow — full size or reducing
5. Equalizer pipe
6. Close nipple at Hartford loop tee to reduce water
hammer potential
7. Condensate return line (gravity or pumped)
8. Pipe to provide 4 inches between water line and top
of Hartford loop return nipple
9. Boiler water line — all automatic water level
controls must be set to maintain this level
10. Minimum 24 inches between water line and bottom
of header
11. O󰀨set tee

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Steam Boiler Piping Guidelines, continued
Pipe Dimensions
Model Riser A Riser B Header H Equalizer J
2194-2594 10" 10" 12" 4"
Figure 11 Models 2194-2594 steam piping – two 10" risers required
Riser A
Riser A
Header H
Header H
Riser B
Riser B
230050
Back
of
boiler
Back
of
boiler
62¾”
62¾”
24” min
24” min
4”
4”
Equalizer J
Equalizer J
Water line
Water line
BOILER
RETURN
10
9
8
7
11
6
5
4
1
3
2
1
Legend – Figure 11, and Figure 12, page 21
1. Riser pipes (one for each supply outlet)
2. Horizontal pipes needed to o󰀨set the header to allow for expansion and contraction of the header
3. Steam supply must be located between last riser connection and equalizer elbow
4. Equalizer elbow — full size or reducing
5. Equalizer pipe
6. Close nipple at Hartford loop tee to reduce water hammer potential
7. Condensate return line (gravity or pumped)
8. Pipe to provide 4 inches between water line and top of Hartford loop return nipple
9. Boiler water line — all automatic water level controls must be set to maintain this level
10. Minimum 24 inches between water line and bottom of header
11. O󰀨set tee