Bring the comparison to the service visit
Keep the old and new product information: size, thickness, rating, brand, and dates used. Share the fault pattern you already observed and any message visible through ordinary viewing access. Do not recreate the shutdown with repeated test runs or remove a filter to prove the theory.
We recommend asking the technician to establish the required airflow and the actual operating condition with the proposed filter. Useful evidence includes filter pressure drop, system static pressure (resistance to airflow), and temperature rise (how much the furnace warms the air passing through it), compared with the exact equipment requirements. These are professional measurements, not a homeowner test list.
The report should explain whether the filter is unsuitable, whether it exposed an existing airflow limitation, or whether another fault is responsible. The remedy might be the supported filter selection or other identified work. It should not start with replacing a protective switch that is responding correctly.
What would change the recommendation?
If the proposed filter is supported and operation still falls outside the model's requirements, changing ratings alone does not close the diagnosis. If the filter is the documented cause, use the specific approved alternative and have proper operation confirmed. Do not adopt a universal MERV cutoff from an online discussion.
For now, follow the service provider's shutdown guidance. Your next action is to request a measured explanation of the limit trip and a written filter specification. The goal is reliable operation with the protective control intact.