Rayburn Thermostat Limit Mx 499K R3943 R5415

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Rayburn Thermostat Limit MX – For 499K (Part No: R3943 / R5415)
Safety Cut-Off Thermostat for Rayburn Oil-Fired Cooker & Boiler Systems

The Rayburn Thermostat Limit MX (Part Numbers R3943 / R5415) is a genuine safety thermostat designed to protect Rayburn 499K oil-fired appliances from overheating. This high-limit cut-off stat monitors boiler temperature and shuts down the burner if temperatures exceed safe operating levels, acting as a crucial safety feature within the appliance’s control system. Ideal for use during servicing or as a direct replacement, this component helps ensure continued safe and reliable operation of your Rayburn system.

Key Features:

• Genuine Rayburn Replacement Part – Designed specifically for 499K MX oil burners

• High-Limit Safety Protection – Prevents dangerous overheating by cutting off fuel supply

• Critical Safety Component – Complies with manufacturer standards for appliance protection

• Reliable Temperature Monitoring – Activates if safe operating thresholds are exceeded

• Easy to Install – Fits directly into compatible control boxes or stat housings

Compatible With:

• Rayburn 499K series oil-fired cookers and boilers

• Models fitted with MX or MX/E burners requiring a limit stat

• Replaces older part numbers R3943 and R5415
  (Always confirm compatibility using your Rayburn’s model number or consult the appliance manual.)

When to Replace the Thermostat Limit:

• If experiencing:

  • Burner lockouts due to false overheat detection

  • No burner operation despite a demand for heat

  • Physical damage, corrosion, or wear to the sensor or wiring

• As part of regular servicing of control system components

• When upgrading or refurbishing older Rayburn models

Tip: Replacing a faulty or ageing limit thermostat is essential for maintaining safe burner control and preventing potential boiler damage or breakdowns.

Technical Specifications:

• Part Numbers: R3943 / R5415

• Function: High-limit safety thermostat

• Application: Rayburn 499K oil-fired models with MX/MX-E burners

• Temperature Range: Factory-calibrated trip point (specific to model design)

• Voltage Rating: 230V AC (standard control system supply)

• Mounting Type: Clip-in or bracket-fixed depending on appliance design

• Reset Type: Manual reset (typical for limit stats – confirm in model specs)