Heated pool and humidity in the house

[Nataly V.]

Dear community,

We are renting a single family house in Florida with pool, which we bought less than year ago and rented. Our tenants were in a house for 8 months and up to this time we promptly responded on all requests.

Recently tenants were out on vacation for a week and after they returned, they discovered that carpet in a house are bulging and we got a complain that humidity is very high in the house (70% and plus). I consulted the prior owner and she told me that it must be that conditioner was not running at proper temperature. When I spoke to tenant he informed us that they set it up on 74 degrees but it was cold during the time so conditioner might not get turned on and therefore humidity got to the point that carpet absorbed the water. This is the second time it happened and we paid for stretching the carpet the first time. In addition, tenant complained that there is a possibly a mold in kitchen grill (dark spots on kitchen grill). We called a HVAC technician for a maintenance and inspection and he indicated that all HVAC systems are working normally and no mold inside the unit or any other issues. He also noted that AC was set on 80 degrees when house was inspected and that tenant took samples of wet dark spots on kitchen grill and send for mold testing and waiting for result.

Tenant told us in past that they that they have a portable dehumidifier and we also sent them Damprids kits.

We are remote owner, obviously not living in a house, and can not control if tenant is using IC or how do they set controls. What is our responsibility as homeowners here and if those demands to fix humidity issues and carpet are reasonable?

Secondary, pool has a not working heater (from the time way back before we purchased the house), which we were not intended to replace originally and tenant indicated first that they don't need a heated in a pool. At the same time with humidity issues, tenant raised the question that pool is not heated and demanded a heater. Same here, is this a reasonable demand? 

Any input/advice is greatly appreciated. Thank you,

Natalie