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A2HIGH

Flue Gas Temperature Too High (Viessmann)

Viessmann boiler flue gas temperature has exceeded the maximum safe limit.

What This Error Code Means

The exhaust gas temperature sensor detected overheating in the flue system.

Common Causes

  • Heat exchanger blocked or scaled
  • Insufficient water flow
  • Circulator pump failure
  • Burner overfiring
  • Combustion settings incorrect

Affected Brands

Viessmann

How ROMA Heating Fixes This

  • Check heat exchanger for blockages or scaling
  • Verify water flow via circulator pump
  • Measure gas pressure and combustion settings
  • Clean or replace heat exchanger if needed
  • Reset and monitor flue temperature

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Available nights, weekends, and holidays. Fast 1-2 hour response.

Licensed Technicians

TSBC Gas License LGA0202903. Fully insured and WCB covered.

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