The landlord, by including the multiple (3-4) air conditioning units in the new lease agreement, would be committing to maintenance and repair for each of the multiple replacement units. Tenants sometimes can be vindictive in causing maintenance issues when in disagreement with the property owner. Check for a reputable landlord protection association for the specific documentation related to tenant maintenance responsibilities.
The new month-to-month lease agreement should state that the tenant is responsible for maintenance and repair of air conditioning units provided as courtesy by landlord. There is no reason to mention the air conditioning units at all in the new lease agreement, except to ensure that the air conditioners units are not removed by the tenant upon the vacating the premises at move-out. (The same reason the refrigerator, range oven, stove top, wall oven, microwave, carpet, etc. are specifically mentioned by brand and model in lease agreement.)
The new month-to-month lease agreement should state that the tenant is responsible for maintenance and repair of air conditioning units provided as courtesy by landlord. There is no reason to mention the air conditioning units at all in the new lease agreement, except to ensure that the air conditioners units are not removed by the tenant upon the vacating the premises at move-out. (The same reason the refrigerator, range oven, stove top, wall oven, microwave, carpet, etc. are specifically mentioned by brand and model in lease agreement.)