The MaXsys S4966V2 (part No 03-25328) is available for ULSA/Rheco units dated from 1st June 2017. Please see the TU-ULSA Burner Control Update (https://www.reznor.co.uk/wp-content/uploads/2025/09/Reznor-TU-ULSA-Burner-Control-Update-UK-Germany-EN-2017-07.pdf) for more information.
Is the MaXsys S4966V2 burner controller still available?
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