Skip to content
Boilers.caby ROMA Heating & Cooling

Viessmann · Error codes

Viessmann Vitodens 200-W N/A 29 — Open Circuit at Terminals 1 and L on the Multi Terminal of the Power Pump Module

N/A 29

Needs attentionVitodens 200-W B2HA large-input boilers (Vitotronic control, B2HA service manuals 5683 702/5685 828/5683 710)

Open circuit at terminals 1 and L on the Multi terminal of the power pump module. There is an open circuit at terminals 1 and L on the Multi terminal of the power pump module, so the burner is in a hold or wait state and the boiler is not displaying a fault; refer to coding address 38:XX and check the connection at terminals 1 and L, including the jumper or installed safety equipment of the Multi terminal of the power pump module. The table classifies it as General.

Applies to

This electronics fault code is displayed by the Vitotronic control (B2HA) on Vitodens 200-W B2HA models (B2HA-285, B2HA-311, B2HA-352, B2HA-399, B2HA-530), as documented in Vitodens 200-W B2HA Service Instructions, sizes 112–150/399/530, doc 5683 710 - 37 (10/2025) — same fault families documented for sizes 19–35 (5683 702 - 17) and 80–100/285–352 (5685 828 - 23) (5683 710 - 37). Codes can differ between controller generations, so always check the manual that matches your unit.

Controller: Vitotronic control (B2HA). Source manual: 5683 710 - 37 (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…

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

Documented for Viessmann Vitodens 200-W (B2HA, 285–530 MBH).

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.

CallEmailEstimate