Viessmann Ignition Electrode With Gasket 7836815

The Viessmann ignition electrode with gasket (part number 7836815) is the spark electrode assembly used to ignite the gas/air mixture in Viessmann Vitodens 200-W B2HA condensing boilers. It mounts on the burner assembly and its gasket seals the electrode against the combustion chamber. The electrode is a service item, replaced when the spark path degrades and ignition becomes unreliable.

• The boiler attempts to fire but does not light, or lights only intermittently.
• The burner locks out repeatedly during the ignition sequence.
• No visible spark at the electrode, or a weak, irregular spark.
• The electrode tip is eroded, contaminated or the ceramic insulator is cracked.
• The electrode gasket is perished, hardened or shows signs of leakage.

• Confirm the boiler model and serial number against the fitment list, as Vitodens 200-W variants use different electrodes.
• Inspect the existing electrode and its gasket before ordering, so the fault is not misdiagnosed as a gas or control issue.
• Check the ignition lead and electrode gap as part of the same service visit.
• Work on the combustion circuit should be carried out by a competent gas engineer.