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NTI Boilers · Error codes

NTI Trinity TRX 1 10 — Supply Sensor Short Circuit or Open Circuit

1 10

Needs attentionNTI Trinity TRX Series I models 150–199C (Series I control, I&O 420011303700)

Supply sensor short circuit or open circuit. The boiler blocked because the supply temperature sensor circuit is shorted or open; likely causes are a blocked plate exchanger or return filter, a disconnected or faulty temperature sensor, or damaged wiring between the supply sensor and the PCB. The table classifies it as Blocking (Auto Reset).

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Applies to

This venting or air-supply fault code is displayed by the TRX Series I control on TRX Series I models from 150 up to 199C (TRX150, TRX199, TRX199C), as documented in TRX 150–199C Installation and Operation Manual, doc 420011303700 Rev 2024.02.16, Part 13-B Boiler Error Codes (420011303700). Codes can differ between controller generations, so always check the manual that matches your unit.

Controller: TRX Series I control. Source manual: 420011303700 (2024-02-16).

Why a code is not a diagnosis

A venting or air-supply code points at the combustion-air path: a blocked terminal, a restricted flue, a failed fan, or a condensate restriction. It does not say which, and running an appliance with a blocked flue is unsafe.

Safe things to observe

  • If a carbon-monoxide alarm sounds anywhere in the building, leave immediately and call 911 from outside.
  • From a safe distance, check that the vent terminal and combustion-air inlet are not blocked.
  • Do not run the appliance while a blockage is suspected.

Do not

  • Do not put anything into the vent or air-intake openings.
  • Do not remove or modify vent pipe.

How professional service helps

  1. A technician inspects the full vent and combustion-air path, clears blockages and checks the fan.
  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.

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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.

Service for this alert

  • Gas Boiler Repair

    Licensed gas technicians from ROMA Heating & Cooling diagnose and repair residential and light-commercial gas boilers across…

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Every boiler part explained — what it does, how it fails and what a technician checks.

Documented for NTI Boilers Trinity TRX.

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.

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Related

Sources and verification

Facts checked September 7, 2026. Last updated September 7, 2026. Technical reviewer: not yet assigned.

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