ventilation and A/C

you’re saying natural air circulation is needed, and A/C can dry up the natural humidity of the wood in few days.
Unfortunately, the master bathroom where your tub is supposed to be located has no natural air ventilation.
It only has A/C. Do you think we are still okay with buying your asunaro tub?
Please let me know what can be the possible issue.

In your case, it is very spacious compared to most bathrooms. Also considering the air volume of the room, the air conditioning should not be a threat for the ofuro but is important that the air stream coming from the AC unit is not pointing directly towards the ofuro.

About the ventilation, air extraction fans tend to exhaust the air near the suction area while the dump air may stagnate under the tub or in narrow gaps.

This is the reason we recommend natural ventilation: because the air moves and forces the humidity out of its “hiding places” and into the exhaust.

A very efficient surrogate of windows is to place a fan or air-circulator on the floor directing the airflow towards the bottom of the ofuro for about 30 minutes after the bath.

It may not be needed because of the NY weather or the good functioning of the exhaust system, but the owner can keep in mind this option and implement it in case the need arises.