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Weil McLain Boiler Parts

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Product Image of Air Pressure Switch, 1.40" W.C., for CGi Boilers (Size 4), 511-624-302
$58.50 each
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Product Image of Automatic Air Vent, Float Type (Boiler Sizes 30-75), 510-148-567
$60.88 each
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Product Image of Sensor/LWCO Wiring Harness, 591-391-995
Sensor/LWCO Wiring Harness, 591-391-995
SKU: 591-391-995
Weil-McLain
SKU: 591-391-995
Brand: Weil-McLain
$19.66 each
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Product Image of Annual Maintenance Kit for AquaBalance 155 Boilers, 640-000-112
$236.40 each
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Product Image of Control Module Assembly for ECO Series 1, 381-330-018
$316.80 each
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Product Image of Cover Plate Gasket for Ultra Gas Boilers (Sizes 155, 230, 310), 383-500-255
$31.87 each
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Product Image of Blower Wheel For HE, HE-II Boilers, 510-312-322
$77.75 each
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Product Image of Air Pressure Switch Kit (0 - 5,500 ft) for GV90+ Boilers, 382-200-723
$39.60 each
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Product Image of Blower Assembly Kit for VHE Boilers, 510-312-317
$450.01 each
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Product Image of Ignition Electrode Gasket, 511-330-253
Ignition Electrode Gasket, 511-330-253
SKU: 511-330-253
Weil-McLain
SKU: 511-330-253
Brand: Weil-McLain
(1)
$11.00 each
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Product Image of Ultra U-control Module Fuses F2 - 12-amp, fast-blow ATO (5 Fuses), 383-500-604
$36.10 each
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Product Image of Water Gauge Glass Cocks - Set (All Boiler Sizes), 510-218-145
$177.54 each
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Product Image of Standing Pilot Wiring Harness for CG, CGA Boilers, 591-391-862
$65.70 each
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Product Image of 12 Liter Expansion Tank - Pre-Charged to 12 psi (3.2 Gallons), 383-700-148
$373.33 each
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Product Image of Gas Valve/Venturi Kit for Ultra Gas Boilers (Size 155), 383-500-025
$387.92 each
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Product Image of Safety Pilot Burner for EGH Boilers (All Sizes) & CGM Boilers (Series 7-10), 511-330-163
$235.80 each
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Product Image of Wiring Harness, 591-391-985
Wiring Harness, 591-391-985
SKU: 591-391-985
Weil-McLain
SKU: 591-391-985
Brand: Weil-McLain
(1)
$46.27 each
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Product Image of Pilot Burner Assembly Kit Intermittant Ignition for LGB, CGi Boilers, 511-330-219
$156.67 each
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Product Image of Natural Gas Pilot Assembly, Standing Pilot, 511-330-186
$72.90 each
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Product Image of 3/8" Glass Rope for Collector Hood, 590-735-109
$17.00 each
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Product Image of Pressure Switch for CGI-6 or 8 , Ser 2 Boiler, 511-624-304
$58.50 each
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Product Image of Heat Exchanger Replacement Kit for Ultra 299, 310 & 399 , 383-500-777
$1,201.21 each
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Product Image of Gas Valve Kit, 383-500-652
Gas Valve Kit, 383-500-652
SKU: 383-500-652
Weil-McLain
SKU: 383-500-652
Brand: Weil-McLain
$1,000.46 each
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Product Image of Gas Valve/Venturi Kit for Ultra Gas Boilers (Size 230), 383-500-030
$396.00 each
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Product Image of Pilot Assembly, 511-330-242
Pilot Assembly, 511-330-242
SKU: 511-330-242
Weil-McLain
SKU: 511-330-242
Brand: Weil-McLain
$99.00 each
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Product Image of Door Seal Rope, 55G, for SGO, WGO, WTGO Boilers, 590-735-104
$23.53 each
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Product Image of Heat Exchanger Replacement Kit for Ultra 155, 383-500-775
$1,207.90 each
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Product Image of Kit-S T-Sensor Water Duplex, 1/2" NPT, 381-330-035
$167.20 each
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Product Image of Combination Pilot Burner Mounting Bracket for LGB Boilers (Sizes 6-12, 13-23), 460-005-624
$17.00 each
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Product Image of Pressure Differential Switch, .90" Setting, for HE/HE II Series 3 (3,4,5), 511-624-511
$95.43 each
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Product Image of UT-1135-605 EG Kit-S Control and Harness, 381-330-031
$276.53 each
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Product Image of 5" Vent Damper Assembly, 381-800-475
5" Vent Damper Assembly, 381-800-475
SKU: 381-800-475
Weil-McLain
SKU: 381-800-475
Brand: Weil-McLain
(3)
$398.95 each
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Product Image of Heat Exchanger Replacement Kit for Ultra 105, 383-500-774
$887.35 each
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Product Image of 48" Thermocouple, Push in, 511-724-253
48" Thermocouple, Push in, 511-724-253
SKU: 511-724-253
Weil-McLain
SKU: 511-724-253
Brand: Weil-McLain
(4)
$44.56 each
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Product Image of Ignition Board, 381-330-027
Ignition Board, 381-330-027
SKU: 381-330-027
Weil-McLain
SKU: 381-330-027
Brand: Weil-McLain
$358.16 each
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Product Image of Kit-S Maint CmPlate EVG 299, 383-900-072
Kit-S Maint CmPlate EVG 299, 383-900-072
SKU: 383-900-072
Weil-McLain
SKU: 383-900-072
Brand: Weil-McLain
$150.89 each
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Product Image of Gas Valve Replacement, 640-000-037
Gas Valve Replacement, 640-000-037
SKU: 640-000-037
Weil-McLain
SKU: 640-000-037
Brand: Weil-McLain
(1)
$520.91 each
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Product Image of Heat Exchanger Replacement Kit for Ultra 230, 383-500-776
$1,269.64 each
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Product Image of ASME Pressure Relief Valve (Boiler Sizes 85-125), 383-600-091
$53.10 each
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Product Image of Bypass Circulator, 511-405-113
Bypass Circulator, 511-405-113
SKU: 511-405-113
Weil-McLain
SKU: 511-405-113
Brand: Weil-McLain
(3)
$314.10 each
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Product Image of Conversion Kit for EG & CG/CGM Boilers (Select Sizes), 510-811-458
$893.56 each
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Product Image of Kit-S FlwMtr T1-T2 WMnt-Combi, 640-000-026
Kit-S FlwMtr T1-T2 WMnt-Combi, 640-000-026
SKU: 640-000-026
Weil-McLain
SKU: 640-000-026
Brand: Weil-McLain
(2)
$112.77 each
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Product Image of Cover Plate Replacement Kit, 383-501-022
Cover Plate Replacement Kit, 383-501-022
SKU: 383-501-022
Weil-McLain
SKU: 383-501-022
Brand: Weil-McLain
(1)
$238.31 each
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Product Image of 3/4" Drain Valve, 511-246-392
3/4" Drain Valve, 511-246-392
SKU: 511-246-392
Weil-McLain
SKU: 511-246-392
Brand: Weil-McLain
(1)
$31.17 each
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Product Image of Condensate Trap Replacement Kit for GV 90+ Boilers, 382-200-415
$60.08 each
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Product Image of Kit-S Flue Temp Sensor WMnt, 640-000-011
Kit-S Flue Temp Sensor WMnt, 640-000-011
SKU: 640-000-011
Weil-McLain
SKU: 640-000-011
Brand: Weil-McLain
(1)
$87.38 each
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Product Image of Kit-S Sensor CH Temp WMnt, 640-000-035
Kit-S Sensor CH Temp WMnt, 640-000-035
SKU: 640-000-035
Weil-McLain
SKU: 640-000-035
Brand: Weil-McLain
$92.79 each
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Product Image of 3" Concentric Vent Termination Kit For Weil McLain Ultra and GV90+ Boilers, 383-500-350
$135.88 each
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More About Weil McLain Boiler Parts

Weil-McLain Boiler Parts cover the components that keep Weil-McLain's cast iron and stainless steel boilers running across the company's residential and commercial product lines. Weil-McLain, headquartered in Burr Ridge, Illinois, describes itself as a leading North American manufacturer of hydronic heating systems, with a lineup spanning residential gas boilers like the CGa and CGi series and Ultra models to commercial units including the SVF stainless vertical firetube line.

Replacement parts for these boilers range from ignition components and control boards to heat exchanger sections and circulator parts, since a cast iron boiler built to last decades often needs individual components replaced well before the boiler itself reaches the end of its service life. Technicians servicing a mixed fleet of Weil-McLain equipment typically stock parts across several model generations, since older cast iron boilers remain in service alongside newer high efficiency models.

Subcategories

  • Ignition and Control Components: Ignition and control components include igniters, flame sensors, and control boards that manage the boiler's start sequence and safety shutoffs. A boiler that fails to light or locks out repeatedly often traces back to one of these parts rather than a larger mechanical failure.
  • Heat Exchanger Parts: Heat exchanger parts cover the sections, gaskets, and seals specific to a cast iron sectional boiler or the tubes and headers used in stainless models like the SVF series. Replacing a cracked section or a failing gasket restores efficient heat transfer without requiring a full boiler replacement.
  • Circulator and Pump Parts: Circulator and pump parts keep hot water moving between the boiler and the building's heating zones, and they see more wear than most other boiler components due to constant operation through the heating season. Technicians commonly stock cartridges, flanges, and seals for the circulator models paired most often with Weil-McLain boilers.
  • Venting and Flue Parts: Venting and flue parts route combustion byproducts safely outside the building, and the specific components depend on whether the boiler uses atmospheric, power vented, or direct vent design. Corroded or damaged venting on an older cast iron boiler needs prompt replacement to keep combustion venting safely.

Buying Guide

Identifying the correct part starts with the boiler's model and series information, typically found on a nameplate attached to the jacket or control panel. Weil-McLain has produced multiple boiler generations over the years, from older cast iron sectional units still running in many buildings to newer high efficiency models like the Evergreen Pro and ECO Tec, and parts are rarely interchangeable across generations.

Cast iron boilers often stay in service for decades, so a technician working on an older unit needs to confirm whether a specific section, gasket, or control component is still produced for that model before promising a repair timeline. Newer boiler generations typically carry a broader current parts inventory, since they remain in active production.

Weil-McLain Boiler Parts split broadly between components shared across a product family, like circulator cartridges and certain control boards, and components specific to a single model, like cast iron sections sized to one boiler's output rating. Confirming which category a needed part falls into before ordering avoids delays from a part that will not fit the installed unit.

Commercial boilers, including the SVF stainless vertical firetube line, generally use different parts than residential cast iron models due to their different construction and larger output range. Technicians who service both residential and commercial Weil-McLain equipment typically maintain separate parts references for each product family to avoid confusion between similar sounding components.

Frequently Asked Questions

How can a technician identify the correct part for an older Weil-McLain boiler?

The model and series information on the boiler's nameplate identifies which parts fit, and checking that information against current parts availability confirms whether an older model's components are still produced. Cast iron boilers especially can span several design generations that are not interchangeable.

Are parts interchangeable between residential and commercial Weil-McLain boilers?

Residential cast iron models and commercial units like the SVF stainless vertical firetube series generally use different parts due to their different construction and output ranges. Checking parts documentation specific to the boiler's product family avoids ordering a component built for the wrong line.

What commonly fails first on an aging cast iron boiler?

Ignition components, control boards, and circulator parts tend to wear out well before the cast iron sections themselves, since those parts see more electrical and mechanical cycling through each heating season. A boiler that locks out repeatedly or loses circulation often points to one of these components rather than the boiler body.

Does Weil-McLain still produce parts for older discontinued boiler models?

Parts availability for discontinued models varies by how long ago a boiler generation was phased out of production, with newer generations generally carrying broader current stock. Confirming availability for a specific older model before committing to a repair timeline helps set accurate expectations.

What venting components need checking during a boiler service call?

Venting and flue components need inspection for corrosion or damage, since the specific parts depend on whether the boiler uses atmospheric, power vented, or direct vent design. A corroded flue on an older cast iron boiler needs prompt replacement to keep combustion venting safely outside the building.