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Mistake & recovery · #088

Wiring a low-voltage thermostat at line voltage, destroying the thermostat

2nd YearSystems & Controls

Low-voltage thermostats typically operate on 24VAC. Line voltage (120V or 240V) will instantly destroy them and is a shock hazard. Always verify voltage a…

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Low-voltage thermostats typically operate on 24VAC. Line voltage (120V or 240V) will instantly destroy them and is a shock hazard. Always verify voltage at the wiring terminals before connecting any thermostat.

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Can you verify this before I keep going? I’m looking at: Wiring a low-voltage thermostat at line voltage, destroying the thermostat. What’s the approved correction for this job?

Do not

Do not hide, force, cover, or “make it work” if this affects safety, access, airflow, rated assemblies, supports, equipment, or inspection. Stop and verify the approved correction.

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