Confirm the exact equipment
Request the full model, current installation instructions, and nameplate electrical requirements. Ask whether the proposed product is designed for a dedicated circuit or an allowed shared-circuit installation. A plug does not answer those questions.
A licensed electrician should assess the existing circuit, panel, service, available space, protection, grounding, and applicable load calculation. Ask which finding requires the upgrade: lack of approved circuit space, inadequate supply capacity, existing damage, or another specific condition.
Do not open the panel or remove covers to prove the point yourself. Provide accessible records and photographs only, and let the electrician establish the actual installation.
Compare supported alternatives
Ask whether another listed heater, an appropriate circuit correction, or a different installation sequence can meet your needs. Request the reason if a panel replacement is necessary and the limits of any less extensive option.
Electrical suitability is only part of the choice. Compare the alternative model's hot-water delivery, reheating, room requirements, and complete cost. A cheaper electrical connection is not a good trade if the selected heater cannot serve the household.
Make the quote specific
Request the load and circuit findings, exact work, responsible electrician, permit and inspection scope, and any other project that affects the decision. If solar, a vehicle charger, or other electrification is planned, give those details to the electrician before finalizing work.
Your next step is to request a written, model-specific electrical finding and a supported alternatives comparison. Decide from that evidence rather than accepting or rejecting a panel upgrade based on voltage alone.