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Lochinvar Knight XL Parameters Progr — After Downloading Parameters From a Laptop the Main Control Board Must Be Reset

Parameters Progr

LockoutLochinvar Knight XL (KBX) commercial boilers (Service Manual Table 3-4 fault codes)

After downloading parameters from a laptop the main control board must be reset. After downloading parameters from a laptop the main control board must be reset, so press the RESET button on the SMART TOUCH display panel. The table classifies it as Lockout (manual reset).

Applies to

This electronics fault code is displayed by the Knight XL control (text faults) on Knight XL models (KBX0400 through KBX1000), as documented in Knight XL (KBX) Service Manual, 100383164 Rev C — Table 3-4 fault codes (100383164 Rev C). Codes can differ between controller generations, so always check the manual that matches your unit.

Controller: Knight XL control (text faults). Source manual: 100383164 Rev C (2025-10).

Why a code is not a diagnosis

An electronics code points at the control board, memory or firmware. It is often triggered by poor incoming power or voltage backfeed from other wiring rather than by the appliance itself.

Safe things to observe

  • Note the code and whether it appeared after electrical work or a power event.

Do not

  • Do not open the control module.
  • Do not repeatedly power-cycle to clear a recurring board code.

How professional service helps

  1. A technician checks supply voltage and grounding, follows the manual's reset sequence and replaces the module only if the code returns.
  2. Combustion and safety devices are verified with an analyser and the manufacturer's procedure after any repair.

Where ROMA provides on-site service

On-site service is currently offered in Greater Vancouver, BC, including Vancouver, Burnaby, Richmond, Surrey, Coquitlam, North Vancouver, West Vancouver, New Westminster, Port Coquitlam, Port Moody, Delta, Langley, Maple Ridge, Abbotsford, Chilliwack, White Rock, Pitt Meadows, Tsawwassen, Anmore, Lions Bay, Belcarra, Bowen Island, Mission. Everything else on this site is reference information you can use anywhere in Canada.

See all service areas

Parts and service

Parts commonly involved

These parts appear in the documented text for this alert. A code reports a condition, not a failed part — a technician confirms the cause by testing before anything is replaced.

Service for this alert

  • Gas Boiler Repair

    Licensed gas technicians from ROMA Heating & Cooling diagnose and repair residential and light-commercial gas boilers across…

  • Emergency Boiler Repair

    Priority gas boiler repair for homes and buildings in Greater Vancouver with no heat, no hot water, a locked-out boiler or a leak.

Every boiler part explained — what it does, how it fails and what a technician checks.

Documented for Lochinvar Knight XL Commercial (KBX).

Frequently asked questions

Can I clear this code myself?

Clearing a code without fixing its cause usually just brings it back. Note the code, check the safe items on this page, then call a licensed technician. If your appliance manual describes a user reset for this exact code and it stays away, no call may be needed.

Boiler locked out? Call with the alert text ready.

The brand, model and this alert are passed along when you request service online, so the technician arrives prepared.

On-site service in Greater Vancouver, BC. ROMA lists “Open 7 days” on its site; call to confirm same-day availability.

Sources and verification

Facts checked September 7, 2026. Last updated September 7, 2026. Technical reviewer: not yet assigned.

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