Weil-McLain ECO Tec LOW WTR CUTOFF OPEN — Internal Low Water Cutoff Contacts Open
LOW WTR CUTOFF OPEN
Internal low water cutoff contacts open. This fault occurs if the internal low water cutoff contacts open, and a manual reset of the control is required while the contacts are open. The table classifies it as Manual reset of control if contacts are open..
Applies to
This low-water or pressure protection code is displayed by the ECO Tec control (display messages) on ECO Tec Series 2 models (80–199 heating-only and 110–199 combi), as documented in ECO Tec Series 2 Boiler Manual, doc 550-100-270/0924 (550-100-270/0924). Codes can differ between controller generations, so always check the manual that matches your unit.
- Weil-McLain ECO Tec
- Weil-McLain ECO Tec 80-H
- Weil-McLain ECO Tec 110-H
- Weil-McLain ECO Tec 150-H
- Weil-McLain ECO Tec 199-H
- Weil-McLain ECO Tec 110-C
- Weil-McLain ECO Tec 150-C
- Weil-McLain ECO Tec 199-C
Controller: ECO Tec control (display messages). Source manual: 550-100-270/0924 (2024-09).
Why a code is not a diagnosis
A water-pressure or low-water code can mean a genuine leak or empty system, a failed expansion tank, a faulty fill valve, or a sensor problem. The appliance does not distinguish these.
Safe things to observe
- Read the pressure gauge and compare it with the normal cold-system pressure your installer set.
- Look for drips or wet spots near the appliance, pipes and the relief-valve discharge.
Do not
- Do not keep re-pressurizing a system that keeps losing water.
- Do not cap a relief-valve discharge pipe.
How professional service helps
- A technician finds and repairs the leak, checks the expansion tank and fill assembly, and verifies the sensor circuit.
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.
Low-water cutoff
A low-water cutoff is the safety device that stops a boiler from firing when there is not enough water inside it.
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…
Every boiler part explained — what it does, how it fails and what a technician checks.
Documented for Weil-McLain ECO Tec.
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
- ECO Tec Series 2 Boiler Manual, doc 550-100-270/0924 · 550-100-270/0924 · accessed September 7, 2026
Facts checked September 7, 2026. Last updated September 7, 2026. Technical reviewer: not yet assigned.