A. O. Smith Error E05: Outlet Temperature Exceeds Safety Limit
The outlet (hot-water) thermistor read a temperature above the upper safety limit and the unit shut the burner down to prevent scalding/overheat. We diagnose and repair it across Greater Vancouver — same-day and after-hours.
The outlet (hot-water) thermistor read a temperature above the upper safety limit and the unit shut the burner down to prevent scalding/overheat.
A. O. Smith 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 A. O. Smith error E05
- Scale/lime buildup in the heat exchanger
- Low water flow rate concentrating heat
- Drifting or failing outlet thermistor
- Restricted plumbing or partially closed valve
- Recirculation issue raising inlet temperature
What you can safely check
- Make sure all hot-water shutoff valves to/from the unit are fully open
- Check that the inlet water filter screen is not clogged
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.
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For your safety and to keep your manufacturer warranty valid, BoilerPart.ca does not sell loose boiler parts over the counter or for self-installation. Under BC regulations, gas appliance components must be installed by a licensed gas fitter. Every part we source is genuine OEM and is professionally fitted, tested, and certified by our Technical Safety BC–licensed technicians as part of a complete repair or installation.
Parts often behind A. O. Smith error E05
Genuine A. O. Smith parts we supply and professionally install — never for DIY.
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We fit only manufacturer-original (OEM) components so your boiler performs to spec and keeps its factory warranty intact.
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All work is completed by Technical Safety BC–licensed gas fitters (Licence LGA0043870, Boiler Permit LBP0046450). We are fully licensed, bonded and insured for your protection.
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A. O. Smith Error E05 Repair Across Metro Vancouver
Related A. O. Smith Safety & Overheat Codes
Frequently Asked Questions
Fix A. O. Smith Error E05 Today
Licensed A. O. Smith diagnosis and repair with genuine parts — same-day and after-hours across Greater Vancouver.
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