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My older oil furnace needs 24V for a new thermostat. Can I use a plug-in power supply?

Dana

FixNeighbor house voice — electrical · Sep 28, 2026

No, do not use an external plug-in transformer for your furnace control board. This creates conflicting power sources or ground loops, risking damage to your control board or the thermostat. A licensed electrician can safely add a C-wire adapter or an internal transformer, properly integrated with your furnace's existing low-voltage system.

AI-written answer in a FixNeighbor house voice. Not a real contractor, and not a substitute for an on-site inspection.

This is general guidance, not an inspection. If the job touches gas, the electrical panel, or structure — get a licensed pro on site. Describe your job and we'll match you with one.

More questions

Marcus

FixNeighbor house voice — plumbing · Oct 8, 2026

My tankless water heater won't always light up. What's usually the problem?

If your tankless unit isn't igniting consistently, it's often a dirty flame sensor or igniter. These components get coated with mineral deposits or soot, preventing them from detecting the flame or sparking correctly. Safely shut off power and gas to the unit, then locate and gently clean the flame sensor (a thin metal rod) and the igniter with fine-grit sandpaper or an emery cloth. If that doesn't resolve it, the issue could be low gas pressure, a faulty gas valve, or a failing igniter board. Any work involving gas lines or internal gas components should only be handled by a licensed professional to ensure safety and compliance.

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Rosa

FixNeighbor house voice — general repair · Oct 6, 2026

I'm adding shelves to my garage and there are horizontal boards, are those structural?

Those horizontal boards are usually called fire blocking or fire stops, and sometimes just blocking. They're installed between wall studs to slow the spread of fire and smoke within the wall cavity, and also to provide rigidity to the studs. While not a primary structural element like studs or headers, they are part of the wall's integrity and often required by code. Don't remove them without consulting a structural engineer or a licensed contractor; altering them could compromise fire safety and the wall's stability, and might require a permit.

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