IBC Technologies · Error codes
IBC SFT-1 F003 — High flue temperature
F003
The controller detected the flue (exhaust) temperature above its safe limit. Flue temperature climbs when the heat exchanger is not absorbing heat properly, which can damage the venting and indicates a combustion problem.
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 SFT-1 tankless water heaters (SFT 199-1), as documented in IBC Installation & Operating Instructions — SFT 199-1 tankless water heater, doc 84160406, sections 5.3.1–5.3.3.
Controller: numeric-display touch panel control. Source manual: 84160406 (2024-09).
Why a code is not a diagnosis
High flue temperature can come from a fouled heat exchanger, wrong fuel setup, improper combustion settings, or restricted venting. The code does not identify which; each is checked on site.
Safe things to observe
- Note the code and do not keep resetting the unit.
- From a safe distance check the vent terminal for blockage.
- If a CO alarm sounds, leave the building and call 911 from outside.
Do not
- Do not run the appliance with a suspected vent or combustion problem.
How professional service helps
- A technician verifies the fuel conversion, combustion readings, and the cleanliness of the heat exchanger and flue passages.
- The fire side of the heat exchanger is cleaned and the cause of the high flue temperature corrected.
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.
Heat exchanger
The heat exchanger is where a boiler transfers heat from the burner flame to the water that heats your home.
What a technician checks →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 →Flue temperature sensor
The flue temperature sensor — sometimes called the stack or exhaust sensor — measures how hot the gases leaving the boiler are.
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.
- Gas Boiler Replacement
ROMA replaces old, failed or inefficient gas boilers in Greater Vancouver, handling removal, venting and gas-supply changes,…
Every boiler part explained — what it does, how it fails and what a technician checks.
Documented for IBC Technologies Superflow SFT-1 Tankless.
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 — SFT 199-1 tankless water heater, doc 84160406, sections 5.3.1–5.3.3 · 84160406 · accessed September 7, 2026
Facts checked September 7, 2026. Last updated September 7, 2026. Technical reviewer: not yet assigned.