Model # 435 FX-R NAT Official Williams wall furnace

Here are the diagrams and repair parts for Official Williams 435-FX-R-NAT wall furnace, as well as links to manuals and error code tables, if available.

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Model diagram and schematic

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ALL PARTS

Showing 10 of 66 parts |

#41

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Thermocouple

Part #P042100

The manufacturer no longer makes this part, and there's no substitute part

#44A

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Cont unit

Part #P271000

The manufacturer no longer makes this part, and there's no substitute part

#43

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Thermostat

Part #P106400

The manufacturer no longer makes this part, and there's no substitute part

#44

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Module

Part #P321096

The manufacturer no longer makes this part, and there's no substitute part

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Vent cover

Part #7B12

The manufacturer no longer makes this part, and there's no substitute part

#10

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Center front panel

Part #12C21

The manufacturer no longer makes this part, and there's no substitute part

#26

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Baffle hndl

Part #11C63

The manufacturer no longer makes this part, and there's no substitute part

#41A

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Furnace burner flame sensor

Part #P271100

The manufacturer no longer makes this part, and there's no substitute part

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Bottom front panel

Part #12B49

The manufacturer no longer makes this part, and there's no substitute part

#13

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Junciton box

Part #12B05

The manufacturer no longer makes this part, and there's no substitute part

Symptoms for gas cooktops

Why won't my cooktop's gas burners ignite or spark?

Main causes: burner igniter switch failure, bad spark module, dirty or damaged spark electrode, wiring failure, lack of …

Why isn't my cooktop's gas burner heating properly?

Main causes: gas supply problem, faulty pressure regulator, clogs in burner or orifice, burner valve failure…

Why do my cooktop's spark igniters keep clicking?

Main causes: stuck burner igniter switch, wet igniter switch contacts, faulty spark module…

How to replace a spark module on a gas cooktop

No flame on your gas cooktop? Installing a new spark module could be the fix you need.…

Repair difficulty

Time required

30 minutes or less

How to replace a spark igniter switch on a gas cooktop

Follow these step-by-step instructions to fix the surface burner ignition system on your gas cooktop by replacing the sp…

Repair difficulty

Time required

45 minutes or less

Articles and videos for gas cooktops

How is cooking on an electric range different than cooking on a gas stove?

Model # 435 FX-R NAT Official Williams wall furnace

Model diagram and schematic

SEARCH WITHIN THIS MODEL

Symptoms for gas cooktops

Why won't my cooktop's gas burners ignite or spark?

Why isn't my cooktop's gas burner heating properly?

Why do my cooktop's spark igniters keep clicking?

Repair guides for gas cooktops

How to replace a spark module on a gas cooktop

How to replace a spark igniter switch on a gas cooktop

Articles and videos for gas cooktops

How is cooking on an electric range different than cooking on a gas stove?

5 Holiday Cleaning Tasks Essential to Boosting Your Home’s Image

How to clean grates and burners on a gas cooktop video

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