Viessmann Vitodens 200-W F.452 — Burner in a Fault State
F.452
Burner in a fault state. There is an error in the scheduled program run monitoring or a synchronization error in the sequence, so reset the appliance and replace the BCU burner control unit if the fault recurs.
Applies to
This fault code is displayed by the HMU/HMI-BCU control (7" touchscreen) on Vitodens 200-W B2HE models (B2HE-85, B2HE-120, B2HE-150, B2HE-199), as documented in Service Instructions — Vitodens 200-W B2HE, doc 6167 813 - 23, troubleshooting fault messages (6167 813 - 23). Codes can differ between controller generations, so always check the manual that matches your unit.
- Viessmann Vitodens 200-W (B2HE)
- Viessmann Vitodens 200-W B2HE-85
- Viessmann Vitodens 200-W B2HE-120
- Viessmann Vitodens 200-W B2HE-150
- Viessmann Vitodens 200-W B2HE-199
Controller: HMU/HMI-BCU control (7" touchscreen). Source manual: 6167 813 - 23 (2026-02).
Why a code is not a diagnosis
The code reports the condition the control detected; the underlying cause must be confirmed on site by a licensed technician using the manufacturer's procedure.
Safe things to observe
- Note the exact code, when it appears and what the appliance was doing.
- If the appliance has stopped, call a technician rather than repeatedly restarting it.
- If you smell gas, stop, go outside and call your gas utility's emergency line or 911 before anything else.
Do not
- Do not ignore a code that returns after a reset.
How professional service helps
- A licensed technician diagnoses the cause with the manufacturer's test procedure.
- 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.
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.
Burner assembly
The burner assembly is where gas and air meet and burn inside a boiler, and its condition decides whether combustion is clean or makes carbon…
What a technician checks →
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 (B2HE).
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
- Service Instructions — Vitodens 200-W B2HE, doc 6167 813 - 23, troubleshooting fault messages · 6167 813 - 23 · accessed September 7, 2026
Facts checked September 7, 2026. Last updated September 7, 2026. Technical reviewer: not yet assigned.