No, you should not run a portable air conditioner vent into a floor ducted heating vent. Portable air conditioners and ducted heating systems are designed to work independently and have different air distribution requirements.
Here's why it's not recommended:
Airflow Direction: Portable air conditioners require a clear path for the exhaust air to be vented outside the room. They come with a flexible exhaust hose that should be directed either through a window, sliding door, or an opening specially designed for the venting kit. Redirecting the exhaust into a floor ducted heating vent would obstruct the airflow, reduce cooling efficiency, and could potentially damage the air conditioner.
Air Pressure Imbalance: Ducted heating systems are designed to distribute heated air evenly throughout your home through the network of ducts. If you were to connect a portable air conditioner's exhaust vent to the heating duct, it could create an air pressure imbalance within the ductwork, leading to poor performance in both the air conditioner and the heating system.
Potential Damage: The moisture and condensation produced by the portable air conditioner might not be compatible with the ducted heating system. Introducing excess moisture into the ductwork could lead to mold growth, corrosion, and damage to the ducts and other components.
If you need to cool multiple rooms or integrate cooling into your existing ducted HVAC system, consider exploring other options like a ducted air conditioning system or a mini-split system. Ducted air conditioning is designed to work with your home's central ductwork, while mini-split systems allow you to cool individual rooms without ductwork modifications.
Always follow the manufacturer's instructions and guidelines for installing and using your portable air conditioner to ensure proper operation and to maintain the warranty. If you're unsure about the best cooling solution for your home, consider consulting with a licensed HVAC professional to get personalized advice and recommendations.