Slant/Fin Error Lockout 174: Safety relay feedback incorrect
The SOLA control detected incorrect safety-relay feedback. Documented causes: a failing limit switch in the ILK circuit (such as the internal LWCO or an external limit wired between R and LIM) or a hardware failure of the SOLA controller. The fix is to check/replace the failing limit, or reset power and, if it persists, replace the SOLA controller. We diagnose and repair it across Greater Vancouver — same-day and after-hours.
The SOLA control detected incorrect safety-relay feedback. Documented causes: a failing limit switch in the ILK circuit (such as the internal LWCO or an external limit wired between R and LIM) or a hardware failure of the SOLA controller. The fix is to check/replace the failing limit, or reset power and, if it persists, replace the SOLA controller.
Slant/Fin fault codes can vary by model and series. Use this as a guide — the same code can have more than one cause. Our Technical Safety BC–licensed technicians read the code, confirm it against your unit's manual, and diagnose the true cause before any repair.
Likely causes of Slant/Fin error Lockout 174
- Failing limit switch in the ILK circuit (internal LWCO or external limit on R-LIM)
- Hardware failure of the SOLA controller
- Intermittent interlock-circuit wiring fault
What you can safely check
- Try a single power-cycle reset of the boiler as the manual suggests
- If the code returns after resetting power, stop and call a licensed technician
Beyond these checks, do not open the unit or touch gas/electrical parts — BC law requires a licensed gas fitter. Call us for a proper diagnosis.
Error Lockout 174 usually leaves you without heat or hot water and can indicate a safety-related fault. Don't keep resetting it — call for priority after-hours Slant/Fin repair.
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Parts often behind Slant/Fin error Lockout 174
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Slant/Fin Error Lockout 174 Repair Across Metro Vancouver
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