IBC Technologies · Error codes
IBC SFC-1 F018 — Flue/combustion air blockage
F018
The controller has detected a restriction in the flue or combustion-air path. The unit stops rather than risk running with inadequate combustion air or blocked exhaust.
If a carbon-monoxide alarm sounds
- Leave the building immediately and get fresh air.
- Call 911. Do not go back inside until emergency services say it is safe.
- Have every fuel-burning appliance inspected before use.
Only after that, call ROMA about the boiler. Official guidance: Health Canada on carbon monoxide.
Applies to
This fault is shown by the numeric-display touch panel control on Superflow SFC-1 combi boilers (SFC 99-1, SFC 125-1 and SFC 199-1), as documented in IBC Installation & Operating Instructions — SFC-1 combi boilers, doc 84156406, sections 5.3.1–5.3.3.
- IBC Technologies Superflow SFC-1 Combi
- IBC SFC 99-1 Superflow
- IBC SFC 125-1 Superflow
- IBC SFC 199-1 Superflow
Controller: numeric-display touch panel control. Source manual: 84156406 (2024-09).
Why a code is not a diagnosis
The blockage can be in the vent pipe, the combustion-air pipe, the terminal, or the fan's backflow flapper. The code does not say where.
Safe things to observe
- From a safe distance, check both the vent terminal and the combustion-air intake for snow, leaves, nests, covers or debris.
- If a CO alarm sounds, leave the building and call 911 from outside.
Do not
- Do not run the appliance while a blockage is suspected.
- Do not put anything into the vent or air-intake openings.
How professional service helps
- A technician inspects the full vent and combustion-air path, clears any blockage, and verifies the fan's backflow flapper operates.
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.
Boiler venting (flue and air intake)
A condensing boiler vents cool, wet flue gases through dedicated plastic pipe that must meet ULC S636 in Canada and the boiler manufacturer's own…
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…
- 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 IBC Technologies Superflow SFC-1 Combi.
Frequently asked questions
What usually blocks a flue?
Snow or ice at the terminal, leaves, bird or rodent nests, and covers or rags left after service are common causes. The terminal should be kept clear, but clearing a blockage inside the pipe is technician work.
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
- IBC Installation & Operating Instructions — SFC-1 combi boilers, doc 84156406, sections 5.3.1–5.3.3 · 84156406 · accessed September 7, 2026
Facts checked September 7, 2026. Last updated September 7, 2026. Technical reviewer: not yet assigned.