Weil-McLain SVF 500 User manual

Models 500 / 600
Commercial Condensing
Gas-Fired Water Boilers
Boiler Manual
Manual Part Number 550-100-273/0523
!
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 can result in severe
personal injury, death, or substantial property damage.

2550-100-273/0523
  500/600  1 
Contents
Abbreviations . . . . . . . . . . . . . . . . . . . . . . 4
Tools . . . . . . . . . . . . . . . . . . . . . . . . . . . 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
Openings . . . . . . . . . . . . . . . . . . . . . . . . . . . .8
Clearances . . . . . . . . . . . . . . . . . . . . . . . . . . .9
Air Openings . . . . . . . . . . . . . . . . . . . . . . . . .10
Preparing for Multiple Boilers. . . . . . . . . . . . . . . . . 11
Prepare the Boiler . . . . . . . . . . . . . . . . . . . 12
Removing the Boiler from the Crate . . . . . . . . . . . . . 12
Placing the Boiler. . . . . . . . . . . . . . . . . . . . . . . 13
Bolting the Boiler to Mounting Blocks . . . . . . . . . . . . 13
Propane Conversion Procedure (when required) . . . . . . . . . 14
High Altitude Installations . . . . . . . . . . . . . . . . . . . . . . 15
Pressure Test Preparation . . . . . . . . . . . . . . . . . .15
Fill the Boiler . . . . . . . . . . . . . . . . . . . . . . . . .15
Pressure Test Precautions . . . . . . . . . . . . . . . . . .16
Perform Hydrostatic Pressure Test . . . . . . . . . . . . . . 16
Install Water Piping . . . . . . . . . . . . . . . . . . 17
General Piping Information . . . . . . . . . . . . . . . . . . 17
Pressure and Temperature Gauge . . . . . . . . . . . . . .17
Relief Valve Installation. . . . . . . . . . . . . . . . . . . . 18
Pipe Sizing . . . . . . . . . . . . . . . . . . . . . . . . . .19
Expansion Tank and Make-up Water . . . . . . . . . . . . . 20
Diaphragm or Bladder Expansion Tank . . . . . . . . . . . 20
Closed-Type Expansion Tank . . . . . . . . . . . . . . . . 20
ZONE VALVE Zoning - General . . . . . . . . . . . . . . . 21
ZONE VALVE Zoning - Primary/Secondary . . . . . . . . . 22
ZONE VALVE Zoning - High-ow-rate or High-head-loss DHW
Circuits . . . . . . . . . . . . . . . . . . . . . . . . . . . .22
ZONE VALVE Zoning - Variable Primary Flow . . . . . . . .23
ZONE VALVE Zoning - Circulator Zoning, Primary/Secondary . . 24
ZONE VALVE Zoning - Radiant Heating, Primary/Secondary . .24
ZONE VALVE Zoning - Water Chiller Systems, Primary/Secondary . 25
Commonwealth of Massachusetts Installations. . . . . 26
Venting and Combustion Air — General . . . . . . . 27
Code Compliance . . . . . . . . . . . . . . . . . . . . . . 27
Venting Methods . . . . . . . . . . . . . . . . . . . . . . .27
Vent and Air Piping . . . . . . . . . . . . . . . . . . . . . .27
Boiler Categories . . . . . . . . . . . . . . . . . . . . . . . 27
Using a Chimney . . . . . . . . . . . . . . . . . . . . . . .28
Combustion Air Contamination . . . . . . . . . . . . . . . . 28
Vent and Air Adapters . . . . . . . . . . . . . . . . . . . . 29
PVC Piping . . . . . . . . . . . . . . . . . . . . . . . . . .29
Venting and Combustion Air Options . . . . . . . 30
Existing Vent System . . . . . . . . . . . . . . . . . . . . . 30
Existing Vent System Test Procedure . . . . . . . . . . . . 30
Vent and Air Piping Materials. . . . . . . . . . . . . . . . . 31
Category II Requirements . . . . . . . . . . . . . . . . . . 32
Vent and Air Terminations for Category IV . . . . . . . . . . 34
Room Air Openings . . . . . . . . . . . . . . . . . . . . . . .35
Combustion Air Provision — Direct Exhaust . . . . . . . . .35
Combustion Air Provision — Direct Vent . . . . . . . . . . .35
Sizing Combustion Air Openings . . . . . . . . . . . . . . . 35
Special Considerations . . . . . . . . . . . . . . . . . . . . 35
Combustion Air Manifold Option – Category IV Only . . . . . 38
DIRECT EXHAUST — Vertical Termination (Cat. II and IV) . 39
Vertical Termination Location . . . . . . . . . . . . . . . . . 39
Multiple Vent Terminations . . . . . . . . . . . . . . . . . . 39
Vent Piping Installation . . . . . . . . . . . . . . . . . . . .40
Vent Termination Installation . . . . . . . . . . . . . . . . .40
DIRECT EXHAUST — Sidewall Termination (Category IV) . .41
Sidewall Termination Location . . . . . . . . . . . . . . . .41
Determine Termination Location . . . . . . . . . . . . . . .42
Multiple Vent Terminations . . . . . . . . . . . . . . . . . . 42
Vent Piping Installation . . . . . . . . . . . . . . . . . . . .42
Vent Termination Installation . . . . . . . . . . . . . . . . .43
DIRECT VENT — Vertical Termination (Category IV). .44
Vertical Termination Location . . . . . . . . . . . . . . . . . 44
Multiple Vent Terminations . . . . . . . . . . . . . . . . . . 44
Vent Piping Installation . . . . . . . . . . . . . . . . . . . .44
Vent and Air Termination Installation . . . . . . . . . . . . .45
DIRECT VENT — Sidewall Separate Pipes (Category IV). . 47
Sidewall Termination Location . . . . . . . . . . . . . . . .47
Determine Termination Location . . . . . . . . . . . . . . .48
Multiple Vent Terminations . . . . . . . . . . . . . . . . . . 48
Vent Piping Installation . . . . . . . . . . . . . . . . . . . .49
Vent Termination Installation . . . . . . . . . . . . . . . . .49
DIRECT VENT — Vertical Concentric (Category IV) . 50
Determine Termination Location . . . . . . . . . . . . . . .50
Multiple Vent and Air Inlet Terminations . . . . . . . . . . . 50
Concentric Piping Termination Installation . . . . . . . . . .50
Vent Piping Installation . . . . . . . . . . . . . . . . . . . .51
Concentric Termination, Typical . . . . . . . . . . . 52
DIRECT VENT — Sidewall Concentric (Category IV). .53
Determine Termination Location . . . . . . . . . . . . . . .53
Multiple Vent and Air Inlet Terminations . . . . . . . . . . . 53
Concentric Piping Termination Installation . . . . . . . . . .54
Vent Piping Installation . . . . . . . . . . . . . . . . . . . .55
DIRECT VENT — Sidewall Vent and Air Plate (Category IV) . . 56
Determine Termination Location . . . . . . . . . . . . . . .56
Multiple Vent Terminations . . . . . . . . . . . . . . . . . . 56
Vent and Air Plate Installation . . . . . . . . . . . . . . . . 57
Vent Piping Installation . . . . . . . . . . . . . . . . . . . .58
Install Condensate Components . . . . . . . . . . . 59
Condensate Trap Installation . . . . . . . . . . . . . . . . . 59
Condensate Line Connection. . . . . . . . . . . . . . . . . 59
Gas Piping . . . . . . . . . . . . . . . . . . . . . . . 60
Gas Supply Piping Connection . . . . . . . . . . . . . . . . 60

3550-100-273/0523
 500/600  1  
Check Natural or LP Gas Supply Pressure. . . . . . . . . . 61
Gas Train Diagram . . . . . . . . . . . . . . . . . . . . . .61
Pipe Sizing for Natural Gas. . . . . . . . . . . . . . . . . . 62
Pipe Sizing for Propane Gas . . . . . . . . . . . . . . . . .62
Multiple Boiler Applications - Manifolded Gas Supply Lines. . 62
Gas Pressure Switches. . . . . . . . . . . . . . . . . . . . 62
– 
Electrical – General . . . . . . . . . . . . . . . . . . 63
Power Requirements . . . . . . . . . . . . . . . . . . . . . 63
Field Wiring . . . . . . . . . . . . . . . . . . . . . . 64
Terminal Connections . . . . . . . . . . . . . . . . . . . . 64
Wiring Overview . . . . . . . . . . . . . . . . . . . . . . . 64
Wire Entrances . . . . . . . . . . . . . . . . . . . . . . . . 64
Wire Routing in the Cabinet . . . . . . . . . . . . . . . . . 64
Schematic Diagram. . . . . . . . . . . . . . . . . . . . . . 66
Ladder Diagram . . . . . . . . . . . . . . . . . . . . . . . 68
Terminal Block Wiring . . . . . . . . . . . . . . . . . . . . 70
Zoning with the Control . . . . . . . . . . . . . . . . 78
– 
Control Setup and Operation . . . . . . . . . . . . . 81
Control Overview . . . . . . . . . . . . . . . . . . . . . . . 81
Control Setup. . . . . . . . . . . . . . . . . . . . . . . . . 81
Control Features . . . . . . . . . . . . . . . . . . . . . . .82
Sequence of Operation. . . . . . . . . . . . . . . . . . . . 83
Control Priorities, Inputs, and Outputs . . . . . . . . . . . .83
Control WIZARD . . . . . . . . . . . . . . . . . . . . . . .83
Control Operation. . . . . . . . . . . . . . . . . . . . . . . 84
Outdoor Temp for Min Target . . . . . . . . . . . . . . . . . 84
Outdoor Temp for Max Target . . . . . . . . . . . . . . . . 84
Outdoor Reset Operation. . . . . . . . . . . . . . . . . . . 84
Remote Target Operation. . . . . . . . . . . . . . . . . . . 85
Remote Modulation Operation . . . . . . . . . . . . . . . .85
Variable Speed Boiler Pumping . . . . . . . . . . . . . . . 85
Essential Control Settings . . . . . . . . . . . . . . . . . . 86
Control Settings Menus. . . . . . . . . . . . . . . . . . . . 87
Connecting the Boiler. . . . . . . . . . . . . . . . . . . . . 88
Contractor Menus . . . . . . . . . . . . . . . . . . . . . . 89
Service Menus . . . . . . . . . . . . . . . . . . . . . . . .89
Startup — Fill the System. . . . . . . . . . . . . . . 90
Clean the System. . . . . . . . . . . . . . . . . . . . . . . 90
Water Chemistry . . . . . . . . . . . . . . . . . . . . . . .90
Freeze Protection. . . . . . . . . . . . . . . . . . . . . . . 91
Antifreeze. . . . . . . . . . . . . . . . . . . . . . . . . . . 91
Fill and Test the Water System . . . . . . . . . . . . . . . . 92
Recommended Inhibitor . . . . . . . . . . . . . . . . . . . 92
Purge Air from the Water System . . . . . . . . . . . . . . 92
Check Concentrations Annually . . . . . . . . . . . . . . . 92
Startup — Final Checks . . . . . . . . . . . . . . . . 93
Check for Gas Leaks . . . . . . . . . . . . . . . . . . . . . 93
Check Thermostat Circuits . . . . . . . . . . . . . . . . . .93
Inspect and Fill the Condensate System . . . . . . . . . . . 93
Inspect the Pressure Switch Hose . . . . . . . . . . . . . .94
Final Checks Before Starting the Boiler . . . . . . . . . . . 94
Startup Procedure . . . . . . . . . . . . . . . . . . . 96
Starting the Boiler . . . . . . . . . . . . . . . . . . . . . . 96
Troubleshooting Startup Issues . . . . . . . . . . . . . . . 96
Check Flame and Combustion . . . . . . . . . . . . . . . .96
Gas Valve Adjustment . . . . . . . . . . . . . . . . . . . . 97
Maximum and Minimum Final Check. . . . . . . . . . . . . 98
Check Ignition System Safety Shuto󰀨 Device . . . . . . . . 98
Check the System for Leaks . . . . . . . . . . . . . . . . .98
Gas Valve Leakage Testing . . . . . . . . . . . . . . . . . 99
Verication Check List . . . . . . . . . . . . . . . . . . . 100
– 
Maintenance — General. . . . . . . . . . . . . . . . 101
Handling Ceramic Fiber Materials . . . . . . . . . . . . . 101
Perform Startup and Checkout . . . . . . . . . . . . . . . 101
Annual Inspection . . . . . . . . . . . . . . . . . . . 102
First-Year Special Inspection . . . . . . . . . . . . . . . . 102
General Inspection Information. . . . . . . . . . . . . . . 103
Inspect the Boiler Area . . . . . . . . . . . . . . . . . . . 103
Inspect the Boiler Interior and Jacket Door Gaskets . . . . 103
Inspect and Clean the Condensate Trap . . . . . . . . . . 103
Inspect All Piping for Leaks. . . . . . . . . . . . . . . . . 103
Service and Maintenance Schedules. . . . . . . . . . . . 104
Annual Startup. . . . . . . . . . . . . . . . . . . . . 105
Check Air Openings . . . . . . . . . . . . . . . . . . . . 105
Flue Vent System and Air Piping . . . . . . . . . . . . . . 105
Check the Water System . . . . . . . . . . . . . . . . . . 105
Check the Boiler Relief Valve. . . . . . . . . . . . . . . . 105
Check the Expansion Tank . . . . . . . . . . . . . . . . . 106
Inspect the Ignition Electrode and Wiring . . . . . . . . . 107
Inspect and Clean the Burner . . . . . . . . . . . . . . . 108
Inspect the Combustion Chamber . . . . . . . . . . . . . 108
Cleaning the Heat Exchanger - Water Side . . . . . . . . 109
Cleaning the Heat Exchanger - Flue Side . . . . . . . . . 109
Reinstalling All Components . . . . . . . . . . . . . . . . 110
Inspecting the High Flue Pressure Switch . . . . . . . . . 112
Replacing the Flue Pressure Switch . . . . . . . . . . . . 112
Check Boiler Wiring and Control Settings . . . . . . . . . 112
Perform Startup and Checks . . . . . . . . . . . . . . . . 112
Low Water Cut-O󰀨 Test. . . . . . . . . . . . . . . . . . . 112
Check the Burner Flame . . . . . . . . . . . . . . . . . . 113
Check the Flame Signal . . . . . . . . . . . . . . . . . . 113
Check the Flue Gas Temperature . . . . . . . . . . . . . 114
Check Blower Speeds . . . . . . . . . . . . . . . . . . . 114
High Altitude . . . . . . . . . . . . . . . . . . . . . . . . 114
Manual Test Mode . . . . . . . . . . . . . . . . . . . . . 116
Reinstall the Jacket Door After Servicing. . . . . . . . . . 116
Review with the Owner . . . . . . . . . . . . . . . . . . . 116
– 
Troubleshooting — General . . . . . . . . . . . . . 117
Diagnosing Boiler Issues . . . . . . . . . . . . . . .117
Checking the Boiler. . . . . . . . . . . . . . . . . . . . . 117
Checking the Control Fuses . . . . . . . . . . . . . . . . 118
Checking the In-Line Fuses . . . . . . . . . . . . . . . . 119
Checking the Temperature Sensors . . . . . . . . . . . . 119
Errors and Lockouts . . . . . . . . . . . . . . . . . 120
Control Fault Indications . . . . . . . . . . . . . . . . . . 120
Fault History Log . . . . . . . . . . . . . . . . . . . . . . 120
Resetting the Control . . . . . . . . . . . . . . . . . . . . 120
Fault and Action Items . . . . . . . . . . . . . . . . . . . 122
(continued on the next page)

4550-100-273/0523
  500/600  1 
– 
Miscellaneous Parts. . . . . . . . . . . . . . . . . . 129
Ordering . . . . . . . . . . . . . . . . . . . . . . . .129
The SVF Commercial Condensing Water Boiler. . . . 130
Replacement Parts . . . . . . . . . . . . . . . . . . 132
Dimensions . . . . . . . . . . . . . . . . . . . . . . 138
– 
Ratings . . . . . . . . . . . . . . . . . . . . . . . . . 139
Read Conguration Settings . . . . . . . . . . . . .140
Bluetooth Connection. . . . . . . . . . . . . . . . . . . . 140
Saving the Boiler Conguration . . . . . . . . . . . . . . 140
Maintenance Log . . . . . . . . . . . . . . . . . . . 142
Installation and Service Certicate. . . . . . . . . . 143
Notes . . . . . . . . . . . . . . . . . . . . . . . . . . . 143

Abbreviation Description
AHD Additional Heat Demand
AMP Ampere or Amperage
ANSI American National Standards Institute
ASME American Society of Mechanical Engineers
BMS Building Management System
BTUH British Thermal Unit per Hour
CAD Combustion Air Damper
CH Comfort Heat
CO Carbon Monoxide
CO2Carbon Dioxide
CP Consumer Protection
CPVC Chlorinated Polyvinyl Chloride
CSA Canadian Standards Association
CSD-1 Controls and Safety Devices
DHW Domestic Hot Water
LP Liqueed Petroleum (Propane)
LWCO Low Water Cut-O󰀨
MBH Thousands of Btuh
NFPA National Fire and Protection Agency
NG Natural Gas
NIOSH National Institute for Occupational Safety
and Health
NTC Negative Temperature Coe󰀩cient
O2Oxygen
ODT Outdoor Temperature
PP Polypropylene
P/T Pressure and Temperature
RPM Revolutions Per Minute
SCFM Standard Cubic Feet per Minute
SS AL29-4C Stainless Steel
TB<#> Terminal Block (1, 2, 3, etc.)
ULC Underwriters Laboratories of Canada
Vac Volts Alternating Current
Vdc Volts Direct Current
W.C. Water Column

Table 2 Common tools needed
Tools Needed Purpose
1/16" at blade
screwdriver
Wiring on terminal blocks. Removing
the throttle screw cover.
3/16" Allen wrench Removing gas valve pressure tap
plugs.
5/16" socket Removing the control panel cover.
T40 bit Removing the o󰀨set cover and
adjusting the o󰀨set screw.
3 mm Allen wrench
Adjusting the throttle screw.
Removing the sight glass, ignitor, or
ame sense rod.
4 mm Allen key
Removing the venturi from the gas
train. Removing the burner access
plate.
5 mm Allen key Removing the cover plate to access
heat exchanger interior.
8 mm socket or
wrench Removing cover plate insulation.
10 mm socket or
wrench Removing the burner.
11 mm socket or
wrench
Removing the venturi from the
silencer.
13 mm wrench Removing the blower.
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.
Table 1 Common abbreviations
Tools

5550-100-273/0523
 500/600  1  
1
2
3
4
5
6
7
8
This section is intended to provide safety information.
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 143. 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. Refer to the
User Manual (part number 550-100-274) for your
reference. 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 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 101.



6550-100-273/0523
  500/600  1 
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 stainless
steel, 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. See pages
90 to 92 for details.
• Before connecting the boiler, thoroughly ush the
system to remove sediment. Install a strainer or other
sediment removal equipment if necessary. The high-
e󰀩ciency 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 make-up water will reduce boiler
life. Mineral buildup in the heat exchanger reduces
heat transfer, overheats the stainless steel heat
exchanger, and causes failure. Addition of oxygen
carried in by make-up water can cause internal
corrosion. Leaks in the boiler or piping must be
repaired at once to prevent make-up 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 26 for sidewall vent air installations.
Freeze Protection Fluids
NEVER use automotive or standard glycol antifreeze,
including glycol made for hydronic systems. Use only
freeze-protection uids recommended in this manual.
See page 91 for more information. Thoroughly
clean and ush any replacement boiler system that
has used glycol before installing the new SVF 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, which will result in 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 can 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.


7550-100-273/0523
 500/600  1  
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 . . . . . . . . . . . . . . . . . . . . . . 12
Install Water Piping . . . . . . . . . . . . . . . . . . . . . . 17
Commonwealth of Massachusetts Installations . . . . . . . 26
Venting and Combustion Air — General . . . . . . . . . . .27
Venting and Combustion Air Options . . . . . . . . . . . . . 30
Room Air Openings. . . . . . . . . . . . . . . . . . . . . . 35
DIRECT EXHAUST — Vertical Termination (Cat. II and IV) . 39
DIRECT EXHAUST — Sidewall Termination (Category IV) . 41
DIRECT VENT — Vertical Termination (Category IV) . . . . 44
DIRECT VENT — Sidewall Separate Pipes (Category IV) . . 47
DIRECT VENT — Vertical Concentric (Category IV) . . . . . 50
Concentric Termination, Typical . . . . . . . . . . . . . . . 52
DIRECT VENT — Sidewall Concentric (Category IV) . . . . 53
DIRECT VENT — Sidewall Vent and Air Plate (Category IV) . 56
Install Condensate Components . . . . . . . . . . . . . . .59
Gas Piping . . . . . . . . . . . . . . . . . . . . . . . . . .60

Installation Compliance Requirements
!
WARNING
Installation and service must be performed
by a qualied installer, service agency, or gas
supplier. Install the equipment in accordance
with this manual to avoid an unsafe operating
condition, which can result in severe personal
injury, death, or substantial property damage.
• Local, state, provincial, and national codes, laws,
regulations, and ordinances.
• National Fuel Gas Code – ANSI Z223.1/NFPA 54,
latest edition.
• National Electrical Code – ANSI/NFPA 70, latest
edition. For Canada, electrical installation and
grounding must be in accordance with Canadian
Electrical Code, Part 1 – CSA C22.1, and local codes.
• For Canada only: Natural Gas and Propane
Installation Code – CAN/CSA B149.1, and local codes.
• 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 SVF boiler manifold and controls met safe
lighting and other performance criteria when the boiler
underwent tests specied in ANSI Z21.13, latest edition.
Checks Before Boiler Installation
1. Check for nearby connections to:
• System water piping
• Venting connections
• Gas supply piping
• Electrical Power
• Location of drain for condensate
2. Check area around boiler. Remove any
combustible materials, gasoline, and other
ammable liquids.
!
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.



8550-100-273/0523
  500/600  1 
1
2
3
4
5
6
7
8
Flooring and Foundation
The SVF 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 2"
(51 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.
1. 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 for U.S.
installations. For Canadian installations, use the
Natural Gas and Propane Installation Code –
CAN/CSA B149.1.
2. Locate or protect the boiler so it cannot be
damaged by a moving vehicle.
3. Ensure that the installation complies with all
applicable codes.
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. See page 10 for more
information.

Table 3 Minimum foundation dimensions
Boiler Model Minimum Dimensions (inches)
SVF 500 29 x 44 x 2
SVF 600 29 x 44 x 2

9550-100-273/0523
 500/600  1  
1
2
3
4
5
6
7
8
Clearances
Hot water pipes, vent pipes, and piping ends all have
a minimum clearance requirement from combustible
surfaces. There are also minimum allowable service
clearances and recommended service access
clearances. See Figure 1 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.
Figure 1 Clearances for SVF Boilers
230006
Top
Top
Left
Side
Left
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
Right
Side
Right
Side
Edge of opening within 12 inches of ceiling.
Edge of opening within 12 inches of ceiling.
Piping end
Rear
Piping end
Rear
Vent
pipe
Vent
pipe
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) 0 24 35
Left side 0 0* 24*
Right side 0 0* 24*
Piping end 18 18 35
(Measured from frame, not pipes)
Top 0 18** 18**
Floor 0 — —
Vent pipe 3/16 — —
Hot water pipes 1/2 — —
* Boiler can be installed next to another boiler. Clearances shown allow for easier service and maintenance.
** Top clearance allows for access to the cover plate for burner and heat exchanger service.

10 550-100-273/0523
  500/600  1 
1
2
3
4
5
6
7
8
Air Openings
Follow the National Fuel Gas Code – ANSI Z223.1/
NFPA 54, latest edition, for the U.S. Follow the
Natural Gas and Propane Installation Code – CAN/
CSA B149.1 for Canada.
Follow all applicable codes to size and verify size
of the combustion and ventilation air openings into
the space.
The SVF boiler requires a special vent system.
See the Venting and Combustion Air sections starting
on page 27 for more information on the venting
methods, and the required air openings and sizing for
direct vent or direct exhaust installations.
SVF Boiler Alone in Boiler Room:
Direct Vent installations: No air ventilation openings
into boiler room are needed if the clearances around
the boiler are at least equal to the recommended
service clearances shown in Figure 1, page 9.
For spaces that do not supply the recommended
minimum service access clearances, see the Room
Air Openings section, starting on page 35 for
required openings.
Direct Exhaust installations: Provide air openings
as specied in the Room Air Openings section,
starting on page 35.
SVF Boiler in a Room With Other Appliances:
Direct Vent installations: Size openings only on
the basis of the other appliances in the space. No
additional air opening free area is needed for the
SVF boiler because it takes its combustion air from
outside.
!
WARNING
For direct vent installations where the boiler is
located in the same room as other appliances,
provide combustion air openings correctly sized
for all appliances in the room EXCEPT the SVF
boiler. Failure to comply can result in severe
personal injury, death, or substantial property
damage.
Direct Exhaust installations: Combustion air
openings into the room must be sized to handle the
SVF boiler and all other appliances. See the Room
Air Openings section starting on page 35 for
required openings.
The boiler control has the ability to operate
a combustion air damper. Refer to section J on
page 74 and the SVF Advanced Manual (part
number 550-100-207).
!
WARNING
For direct exhaust installations, provide
combustion air openings correctly sized for all
appliances in the room, INCLUDING the SVF
boiler. Failure to comply can result in severe
personal injury, death, or substantial property
damage.


11550-100-273/0523
 500/600  1  
1
2
3
4
5
6
7
8
Preparing for Multiple Boilers
1. Provide the clearances shown in Figure 2 and
follow local codes. Other layouts can be used if
all required clearances are maintained.
2. Construct boiler foundation if the oor in the boiler
room is uneven or if there is the probability of
ooding. Size foundation to allow for clearance
and spacing dimensions shown in the gure
below.
3. Chalk-line boiler locations on foundation or boiler
room oor.
4. Remove boilers from the crate and assemble
according to instructions in this manual.
5. Provide clearance for installation of venting,
air piping, gas piping, condensate piping and
components, expansion tank, boiler pump, and
other accessories as given in Figure 1, page 9.
Figure 2 Side-to-side mounting of multiple boilers
Minimum Allowable Service
230007
0” or 24"
(or as required
by codes)
0” or 24"
(or as required
by codes)
24"
(or as required
by codes)
0”
(or as required
by codes)
0”
(or as required
by codes)
18" minimum for combustible surfaces
(or as needed for piping or code requirements)
Recommended set up
35" (or as required by codes)
24"
(or as
required
by codes)
24"
(or as
required
by codes)
24"
(or as
required
by codes)
24"
(or as
required
by codes)
35" minimum recommended for service
(or as needed for piping or code requirements)

12 550-100-273/0523
  500/600  1 
1
2
3
4
5
6
7
8

Removing the Boiler from the Crate
Leave the boiler in the crate pallet until ready to place
in the nal location. Follow all uncrating instructions.
Refer to Figure 3 for the following instructions.
NOTICE
If the boiler has been stored in a location with
temperatures below 32°F (0°C), handle with care until
the plastic components come to room temperature.
NOTICE
Leave the plastic covers on the connections and
adapters until ready to attach piping. This will protect
the tting surfaces from damage and prevent debris
from entering the vent or air adapters.
1. Move the crate to a solid, level surface. The crate
must sit securely on the ground. Ensure there is
su󰀩cient clearance for the crate, ramp, and nal
boiler placement on the oor in front of the piping.
!
WARNING
The boiler is heavy. Use caution not to drop
the boiler. Use proper lifting equipment and
techniques. Do not lift the boiler with water or gas
pipes. Do not handle, apply weight to, or push
on the gas pipes. Failure to comply can result
in severe personal injury, death, or substantial
property damage.
2. Remove the ramp from the crate. Place the end
of the ramp into the notch in the pallet as show in
Figure 3. Follow the uncrating instruction label to
secure the ramp to the pallet.
3. Remove the eight screws and eight lag bolts from
the four shipping brackets.
Figure 3 SVF boiler on pallet with ramp in position
230008
Ramp
Pallet
Apply pressure only to jacket
corners when moving
Notch
Hex head bolts
3/8" wrench
Lag bolts
7/16" socket or
wrench
Shipping brackets
(right & left sides)

13550-100-273/0523
 500/600  1  
1
2
3
4
5
6
7
8
Placing the Boiler
1. Roll the boiler down the ramp and move the boiler
into position. The boiler must be unloaded from
the pallet onto a solid, level surface.
!
WARNING
The boiler is heavy. Use caution when rolling
down the ramp. When moving the boiler, apply
pressure ONLY at the jacket corner posts or
water manifolds. Handling the boiler improperly
can result in severe personal injury, death, or
substantial property damage.
2. The front two casters are swivel type, while the
back two casters are xed. Take care to keep the
boiler straight when rolling.
3. Adjust the leveling legs down until they are rmly
in contact with the oor. Remove the jacket
panels to access bolt heads and jam nuts for
leveling the boiler.
4. Continue adjusting the legs until the bottom of
the boiler base is 1/16" (1.6 mm) above the oor
while keeping the boiler level. Check the level,
front to back and side to side. Measure level on
the cover plate. See Figure 4.
CAUTION
!
Do not rest the boiler on the casters. The casters
are intended for moving the boiler into position
only. The support legs must be extended to take
the load o the boiler.
Bolting the Boiler to Mounting Blocks
For applications requiring bolting down of the boiler
(such as earthquake zone requirements), use the
leveling legs to position the boiler until the bottom
of the boiler base is 1/16" (1.6 mm) above the oor.
The four brackets used as seismic mounting brackets
are also used as shipping brackets. Reattach these
brackets with the eight screws and eight lag bolts
once the boiler is in place. See Figure 3, page 12
and Figure 5 for details. Refer to the seismic
calculations document for additional information.
!
WARNING
Follow all applicable codes and recognized
engineering design practices to verify the nal
mounting will meet all seismic, structural, and
other requirements. Failure to comply can result
in severe personal injury, death, or substantial
property damage.
230009
Leveling
Legs (x4)
Leveling
Legs (x4)
Brackets (x4)Brackets (x4)
Installation is NOT complete until the leveling legs are
lowered below the wheels. The wheels MUST be lifted off
of the ground. Refer to manual for minimum distance
required.
550-225-451 (0522)
WARNING
LEVELING LEGS
Figure 4 Leveling legs warning
Figure 5 Seismic mounting brackets (provided by others)

14 550-100-273/0523
  500/600  1 
1
2
3
4
5
6
7
8
Propane Conversion Procedure (when required)
All SVF boilers are shipped ready for natural gas
operation. The boilers must be tted with a propane
orice and propane venturi to be used with propane.
A conversion kit to convert the boiler to propane is
purchased separately (part number 384000423). See
Miscellaneous Parts on page 129.
!
WARNING
Turn o electrical supply to installed boilers
before service. Close the external manual
gas shut-o valve to isolate the boiler during
conversion. Allow the boiler to cool if it has been
operating. Failure to follow these instructions
can result in severe personal injury, death, or
substantial property damage.
1. Shut o󰀨 power to the boiler before service.
2. Locate the propane orice plate and the propane
venturi from the conversion kit bag.
3. Verify that the stamping on the orice plate is
correct for the model size. There is one orice for
the SVF 500/600 boiler. The orice size is 0.494".
4. Verify the orice sizes on the venturi. The top
orice is 7.0 mm and the bottom orice is 8.4 mm.
a. Ensure the label on the venturi reads:
VenturiØ: 45
InjØ: 840/700
!
WARNING
The propane orice size marking must match
the required boiler orice size. Incorrect sizing
can cause leaking gas fumes, which can result in
severe personal severe personal injury, death, or
substantial property damage.
5. Make a coarse throttle adjustment to the gas valve.
a. Carefully open the throttle fully.
b. Close the throttle 4 and 7/8 turns.
6. Remove the two top panels from the boiler and set
aside. Remove the side panels for easier access.
7. Using two 8 mm wrenches, remove the four bolts
holding the silencer to the venturi.
8. Using two pipe wrenches, disconnect the gas ex
line from the inlet pipe of the automatic gas valve.
9. Using an 8 mm wrench and 4 mm Allen wrench,
remove the four bolts holding the gas pipe to the
bottom of the venturi. A gasket will come free.
10. Remove the venturi with O-ring from the blower with
a 13 mm wrench. Set the venturi aside. Ensure the
O-ring is in good condition. Replace if necessary.
11. Take the propane venturi from the kit and install
it to the blower. Ensure that the gas hookup is in
the down orientation, and the O-ring is seated
properly between the blower and venturi. Use
a 13 mm wrench to secure the three nuts to
the studs that hold the venturi to the blower.
These blower studs should be equally spread
out at 120° intervals, at the 12, 4 and 8 o'clock
positions. Tighten to 87 in-lbs (9.82 Nm).
12. Install the propane orice between the gas pipe
and the bottom of the venturi, wedged between
the two square gaskets supplied with the propane
conversion kit. See Figure 6. Secure the gas pipe
to the venturi with an 8 mm wrench and a 4 mm
Allen wrench and tighten to 70 in-lbs (7.90 Nm).
13. Install the silencer to the venturi. Secure the
silencer with the four previously removed bolts
using two 8 mm wrenches. Tighten to 70 in-lbs
(7.90 Nm).
14. Reconnect the gas ex line to the inlet pipe of the
automatic gas valve.
15. Apply the conversion label next to the rating label.
16. Reconnect the power to the boiler.
Test the boiler completely after conversion. Fill
out the Fire Test label with the test results. Follow
all instructions in this manual to start up the boiler.
Check combustion levels and verify operation of the
boiler and all system components after conversion.

Figure 6 Propane orice location
Mixer
Mixer
Square
Gaskets
Square
Gaskets
Propane Orifice
Propane Orifice
Gas Piping
Gas Piping
230106

15550-100-273/0523
 500/600  1  
1
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3
4
5
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7
8
High Altitude Installations
For high altitude installations (over 2,000 ft.),
maximum blower, minimum blower, and ignition RPM
must be updated according to Table 18, page 115.
If using propane as the input gas, target CO2
values must also be adjusted according to the table.
Make sure the boiler is converted to propane per the
instructions on page 14.
Pressure Test Preparation
Do not install the relief valve until pressure testing is
complete. See Relief Valve Installation on page 18
for installation instructions and warnings.
IMPORTANT
Apply pipe dope on all connections in the following
steps. Use pipe dope sparingly.
Reference Figure 7 for the following steps. All
components in this section are provided by the
installer except a 30 psig relief valve and the P/T
gauge.
1. Remove the relief valve if it is installed.
2. On the boiler supply pipe, install two tees as
shown in Figure 7. Orient the tee closest to the
boiler up into a vertical position. Install the second
tee in a horizontal position.
a. The tee in the vertical position is where the
relief valve will be installed after the pressure
test. Install an NPT plug in this location for the
pressure test.
b. The tee in the horizontal position is where the
P/T gauge is installed for testing and for normal
boiler operation.
3. Install a shut-o󰀨 valve on the supply side and
connect it to the rest of the system piping.
4. Install a drain valve and a shut-o󰀨 valve on the
boiler return pipe before connecting to the rest
of the system piping. See Figure 7 for the boiler
drain location.
5. If the pressure test is conducted with a pressure
over 160 psig, remove the automatic air vent
located inside the boiler cabinet on the heat
exchanger port; replace it with a 1/2" NPT plug.
Fill the Boiler
1. Open the shut-o󰀨 valves installed on the supply
and return connections.
2. Allow water to ow into the bottom connection
and air to ow out the top connection.
3. When water reaches the shut-o󰀨 valve on top,
allow water to ow long enough to ensure all air is
out of the heat exchanger.
4. Close the shut-o󰀨 valves on supply and return
lines.
5. Close o󰀨 the water supply.
P/T Gauge
P/T Gauge
Relief Valve
(installed after testing)
Relief Valve
(installed after testing)
230107
Boiler Drain
Boiler Drain
Figure 7 Hydrostatic test piping connections - anges,
valves, and gaskets provided by installer

16 550-100-273/0523
  500/600  1 
1
2
3
4
5
6
7
8
Perform Hydrostatic Pressure Test
1. Use the hand pump to raise water pressure for
testing.
2. The test pressure should be 1.5 times the
pressure setting of the relief valve.
3. Gradually apply pressure until test pressure is
reached. Test pressures are shown in Table 4
and are compared to the normal operation of the
boiler with the pressure relief valve installed.
4. Hold at test pressure for 10 minutes.
5. Maintain constant gauge pressure throughout the
test.
6. Check for leaks. Repair any leaks from threaded
joints. If leaks are found in the heat exchanger,
consult your WM Technologies representative.
7. Slowly release pressure and drain.
8. Install the automatic air vent if removed.

Pressure Test Precautions
!
WARNING
Failure to comply with these precautions can
result in severe personal injury, death, or
substantial property damage.
All air MUST be purged out of the heat
exchanger before performing the hydrostatic
pressure test.
The test pressure MUST NOT exceed the
maximum pressure on the P/T gauge. If the
test pressure is going to exceed the maximum
range of the current P/T gauge, use an
appropriate gauge for the test.
Leaks must be repaired immediately. Leaks
can damage the boiler, leading to substantial
property damage.
DO NOT leave the boiler unattended at any
time during testing. A cold water ll could
expand and cause excessive pressure,
resulting in severe personal injury, death, or
substantial property damage.
The release of high pressure water should
be done in a safe manner. Failure to release
the water safely can result in severe personal
injury, death, or substantial property damage.
DO NOT use petroleum-based cleaning or
sealing compounds in the boiler system.
Gaskets and seals in the system may be
damaged, resulting in substantial property
damage.
Table 4 Test pressure
Relief Valve Pressure Test Pressure
30 psig 45 psig
50 psig 75 psig
100 psig 150 psig
160 psig 240 psig

17550-100-273/0523
 500/600  1  
1
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5
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General Piping Information
NOTICE
Use two wrenches when tightening water piping
at the boiler with one at the boiler interior piping to
prevent it from turning. Failure to prevent boiler piping
connections from turning could cause damage to
boiler components.
Additional controls, when required:
The control module uses temperature sensors to
provide both high limits protection and operating limit
control. The module is UL353 Limit Controls certied
to meet ASME CSD-1 and Section IV requirements.
A manual reset of the equipped low water cut-o󰀨
(LWCO) is performed through the control module.
Some codes and jurisdictions may require additional
external controls.
Operating limit set point =
Supply Max. Temperature + O󰀨 Di󰀨erential
Additional limit controls:
• Consult local requirements for other codes and
standards to determine if additional limit devices
are needed.
• The control provides two sets of limit control
contacts. One set will cause automatic reset, while
the other will cause manual reset of the control.
See the Field Wiring section starting on page 64
for wiring information.
• The control can be reset using the manual RESET
function on the control display.
NOTICE
If the heating system includes circuits that require
lower temperature water along with circuits that
require higher temperature water, it is recommended
to protect low-temperature circuits with limit controls
that are wired to a manual or automatic reset circuit
on the control.
Low water cut-o󰀨:
A push-to-test LWCO is factory installed on the switch
panel on the left side of the control tray. See Figure 8.
The LWCO probe is mounted on the front of the
heat exchanger.
The LWCO is manually reset through the main
control. This can be performed through the display by
selecting <Reset Lockout>.
Backow preventer:
Use a backow check valve in the water ll as
required by local codes.
Pressure and Temperature Gauge
The boiler is shipped with a 1/4" NPT pressure and
temperature (P/T) gauge. The gauge has a pressure
range up to 75 psig. This gauge meets ASME
requirements for a relief valve setting of up to 50 psig.
The P/T gauge is mounted in a horizontal tee on
the boiler supply outlet pipe. Installer must supply
a tee connected to the system supply that has the
correct sizing for the necessary P/T gauge. See
Figure 7, page 15 for placement details.

Figure 8 LWCO test button location
230126 LWCO Test Button

18 550-100-273/0523
  500/600  1 
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
Relief Valve Installation
!
WARNING
Do NOT install a relief valve with a pressure
higher than 160 psig. This is the maximum
allowable relief valve setting for the SVF boiler.
The boiler is shipped with a 30 psig relief valve.
Failure to comply can result in severe personal
injury, death, or substantial property damage.
!
WARNING
Improper installation of the relief valve and
discharge line can cause water damage and
scalding. Follow all instructions and guidelines
below and in this manual. Failure to comply
can result in severe personal injury, death, or
substantial property damage.
1. A 30 psig relief valve is shipped with the boiler.
The valve must be installed by a qualied
installer. The valve should be connected as close
to the boiler water outlet as possible.
2. Connect discharge piping to a safe disposal
location according to the guidelines below.
• Discharge line must be connected to the relief
valve outlet and run to a safe place of disposal.
Terminate the discharge line in a manner that will
prevent the possibility of severe burns or property
damage should the valve discharge.
• Discharge line must be as short as possible and
be the same diameter as the valve discharge
connection throughout its entire length.
• Discharge line must pitch downward from the
valve and terminate at least 6" above the oor drain
where any discharge will be clearly visible.
• Discharge line shall terminate plain, not threaded,
with a material serviceable for temperatures of
375°F (191°C) or greater.
• Do not pipe the discharge to any place where
freezing could occur.
• Do not install any shut-o󰀨 valve between the relief
valve and boiler, or in the discharge line. Do not
plug or place any obstruction in the discharge line.
• After lling and pressurizing the system, test the
operation of the valve by lifting the lever. Make
sure the valve discharges freely. If the valve fails to
operate correctly, replace it with a new relief valve.
Figure 9 Relief Valve Installed
230108
Relief Valve,
installed

19550-100-273/0523
 500/600  1  
1
2
3
4
5
6
7
8
Pipe Sizing
Size the piping and the pumps to provide the required
temperature rise. See Figure 10 for boiler head loss
curves. See Table 5 for maximum and minimum ow
rate through the boiler and head loss versus ow rate.
NOTICE
Pipe sizing should be based on the desired
temperature rise for the system, corresponding to the
recommended maximum ow rate. Failure to follow
these guidelines can result in system issues.
NOTICE
DO NOT design the piping and components for a
boiler ow rate above or below the ranges given in
Table 5 without using one of the piping strategies
listed below. Insucient ow will cause nuisance
outages due to limit operation. Excessive ow can
damage the boiler heat exchanger from erosion.
Size system piping per Table 6, or apply recognized
engineering practices to size the piping.
IMPORTANT
The SVF 500 and 600 boilers have 2" NPT male
connections. Installer to provide reducers to adapt
from external piping to the boiler supply and return
connections if the system allows.
Higher ow rates than shown in Table 5:
• Use Primary/Secondary piping. See pages 22,
24, and 25.
• Add a di󰀨erential pressure bypass valve to
bypass the excessive ow in a Variable/Primary
ow system, or provide an alternative engineering
solution. See the gures on page 23.
Lower ow rates than shown in Table 5:
• Use Primary/Secondary piping.
• In a Variable/Primary ow system, it is
recommended to install a ow switch that is set at
the minimum ow rate of the boiler. The variable
circulator will increase water ow and prevent the
boiler from ring with an insu󰀩cient ow rate. The
higher water ow will make the ow switch contact,
which will start the boiler.
Sch 40 Pipe
Diameter
Maximum
Flow Rate
GPM
SCH 40 Pipe
Diameter
Maximum
Flow Rate
GPM
2 45 6 800
3 140 8 1650
4 290 10 3000
5 500 12 4750
Figure 10 Pressure drop versus ow rate for SVF boilers
Table 5 Flow rate and pressure drop data
Table 6 Recommended pipe sizing per ow rate
0
5
10
15
20
25
30
35
40
0 10 20 30 40 50 60 70 80 90
P
r
e
s
s
u
r
e
D
r
o
p
(
f
t
)
Flow (gpm)
SVF 500/600: Pressure Drop vs. Flow
Pressure Drop (ft)
230080
SVF 500
Minimum Water
Pressure GPM 100% Rate Boiler Head Loss (Feet W.C.)
Temp Rise (°F)
10 PSI
48 20 7.5
38 25 4.7
32 30* 3.5
27 35 2.8
24 40 2.3
21 45 2.1
19 50 1.9
17 55 1.7
16** 60 1.6
SVF 600
Minimum Water
Pressure GPM
100% Rate Boiler Head Loss
(Feet W.C.)
Temp Rise (°F)
10 PSI
57 20 11.9
46 25 6.8
38 30* 4.7
33 35 3.6
29 40 3.0
25 45 2.5
23 50 2.2
21 55 2.0
20** 60 1.9
* Suggested design ow rate (30°F temp, rise, water only)
** Minimum Flow Rates (GPM):
SVF 500: High Fire = 16, Low Fire = 4
SVF 600: High Fire = 20, Low Fire = 4

20 550-100-273/0523
  500/600  1 
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8
Expansion Tank and Make-up Water
Ensure the expansion tank size will handle boiler and
system water volume and temperature. See Table 26,
page 139 for boiler water content.
The expansion tank must be located as shown in
this manual or per recognized design methods. See
the tank manufacturer's instructions for details.
NOTICE
Undersized expansion tanks cause system water loss
from the relief valve, and make-up water to be added
through the ll valve. Boiler failure can eventually
result due to the excessive addition of make-up
water.
Connect the expansion tank to the air separator
only if the separator is on the suction side of the
pump. Always install the system ll connection at the
same point as the expansion tank connection to the
system.
Most piping drawings in this manual show
diaphragm expansion tanks. See Figure 12 for piping
from the air separator to the expansion tank and
make-up water line using a closed-type expansion
tank.
Most chilled water systems are piped using a
closed-type tank. Refer to Figure 19, page 25.
Diaphragm or Bladder Expansion Tank
Always install an automatic air vent on top of the air
separator to remove residual air from a system with a
diaphragm or bladder expansion tank. See Figure 11.
NOTICE
When the boiler is installed above the system main
piping using diaphragm or bladder tanks, install an
automatic air vent in the top of the outgoing boiler
piping to prevent air pocketing.
NOTICE
The expansion tank needs to be charged to the
required system ll pressure before being connected
to the system.
Closed-Type Expansion Tank
Refer to Figure 12 for piping connections when using
a closed-type expansion tank.
Pitch any horizontal piping up towards the tank.
Pitch at 1" per 5 ft. of piping. Connect to the tank with
at least 3/4" piping to allow room for air to rise.
NOTICE
DO NOT use automatic air vents on closed-type
expansion tank systems. If there is an automatic
air vent installed on the heat exchanger, remove
it before operation. Air must remain in the system
and return to the tank to provide its air cushion. An
automatic air vent would cause air to leave system,
resulting in water-logging the expansion tank.

Figure 11 Expansion tank piping - diaphragm-type tank
220066a
T
o system
From boiler/system 7
1
3
4
5
8
Figure 12 Expansion tank piping - closed-type tank
To systemFrom boiler/system
2
3
6
7
8
220066b
Legend – Figure 11 & Figure 12
1. Diaphragm -type expansion tank
2. Closed-Type expansion tank
3. Make-up water line
4. Fill valve, typical
5. Air separator
6. Tank tting
7. System pump (when used)
8. Automatic air vent