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NTI Boilers · Error codes

NTI Trinity TFT 183 — Lead Lag P-gain Was Invalid

183

Needs attentionNTI Trinity TFT legacy boilers (TFT control; hold/lockout and alert tables, I&O 99984535)

Lead Lag P-gain was invalid. The control recorded this alert for Lead Lag P-gain was invalid, and alert code 183 is listed in Table 16-4 Alert Codes. The table classifies it as Alert.

Applies to

This fault code is displayed by the TFT control (Honeywell SOLA) on TFT models (TFT60, TFT85, TFT110, TFT154, TFT201, TFT285, TFT340, TFT399), as documented in Trinity TFT60-399 Installation and Operation Manual, doc 99984535 (2024-04-08), sections 16.1–16.3 (99984535). Codes can differ between controller generations, so always check the manual that matches your unit.

Controller: TFT control (Honeywell SOLA). Source manual: 99984535 (2024-04-08).

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

  1. A licensed technician diagnoses the cause with the manufacturer's test procedure.
  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

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.

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