NTI Flame Loss: Flame Loss During Operation

What the NTI Flame Loss fault means, what causes it, and why it's a job for a licensed BC gas technician — not a DIY reset.

Severity

High — needs prompt professional attention

Flame failure

Gas safety first

This fault involves gas, combustion or venting. If you smell gas (rotten-egg odour), hear hissing, or feel unwell, leave the building immediately and call 911 or FortisBC at 1-800-663-9911 from outside. Do not flip switches or relight anything. For all other cases, switch the boiler off and call a licensed gas technician.

What the NTI Flame Loss fault means

The burner lit but the flame signal dropped out mid-cycle, so the NTI control shut the boiler down rather than run blind.

On NTI TFTN (Trinity Fire Tube), FTVN and TRX condensing boilers, Flame Loss is a flame failure. It is a protective response — the boiler is telling you something needs attention, and the safe, lasting fix is a proper diagnosis rather than repeated resets.

Symptoms you may notice

  • Boiler fires briefly then shuts down
  • Intermittent heat or hot water
  • Short-cycling with lockouts

Common causes of NTI Flame Loss

Degraded flame-sensing electrode or poor grounding
Fluctuating gas supply
Flue gas recirculation or venting fault
Condensate blockage

Why this is not a DIY fix

Loss-of-flame and false-flame faults point to the flame-rectification circuit, a dirty flame sensor, a failing gas valve, or unstable combustion. Confirming the cause needs live flame-current (microamp) readings and combustion analysis — instrumented gas work reserved for licensed technicians.

In British Columbia, gas work must be performed by a TSBC-licensed gas fitter. GasBoilers.ca — a CanroHeat division — sends Red Seal–certified, gas-licensed technicians who diagnose the true cause, repair it correctly, and verify safe operation before they leave.

How our technicians diagnose & repair it

  1. 1Measure flame-rectification current (microamps) during firing
  2. 2Clean or replace the flame-sensing electrode and check its ground path
  3. 3Inspect the burner and heat exchanger for sooting or fouling
  4. 4Verify gas pressure and re-run combustion analysis

NTI Flame Loss — FAQ

What does the NTI Flame Loss fault mean?

The burner lit but the flame signal dropped out mid-cycle, so the NTI control shut the boiler down rather than run blind. On NTI TFTN (Trinity Fire Tube), FTVN and TRX condensing boilers, this is categorised as a flame failure.

What causes NTI Flame Loss?

The most common causes are: Degraded flame-sensing electrode or poor grounding; Fluctuating gas supply; Flue gas recirculation or venting fault; Condensate blockage. A licensed technician confirms which one applies before any part is replaced.

Can I fix NTI Flame Loss myself?

No. Loss-of-flame and false-flame faults point to the flame-rectification circuit, a dirty flame sensor, a failing gas valve, or unstable combustion. Confirming the cause needs live flame-current (microamp) readings and combustion analysis — instrumented gas work reserved for licensed technicians. Repeatedly resetting the boiler without fixing the root cause can be unsafe and can cause further damage. Call GasBoilers.ca at 604-359-1081 for a licensed diagnosis.

Is the NTI Flame Loss fault dangerous?

It can be. This fault involves combustion, gas or venting. If you ever smell gas, leave the building immediately and call 911 or FortisBC at 1-800-663-9911 from outside. Otherwise, switch the boiler off and book a licensed technician.

How much does it cost to fix NTI Flame Loss in Greater Vancouver?

Cost depends on the root cause and any parts needed. We start with a flat-rate diagnostic, then quote the repair before any work begins — no surprises. Call 604-359-1081 for current pricing and same-day availability.

NTI showing Flame Loss? We'll fix it right.

Licensed, Red Seal–certified gas technicians across Greater Vancouver. Upfront pricing, same-day service available.

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