Tankless Water HeaterEmergency2026-01-09
Tankless No Hot Water Emergency
Sudden loss of hot water from a tankless unit — quick checks and when to call for emergency help.
Losing hot water suddenly from a tankless unit is disruptive. A few checks may restore it; otherwise it's a priority repair.
Quick checks
Confirm power and gas are on (test another gas appliance), check the display for an error code, ensure the cold-water inlet valve is open, and clean the inlet filter if accessible.
When to call
If there's an error-code lockout, no ignition, or a leak, call for service. Note the brand and code so we can come prepared.
Key takeaways
- Check power, gas and the inlet valve
- Note the error code and brand
- Clean the inlet filter if you can
- Call for priority service if it won't restart
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Frequently asked questions
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