In a warm air heating system, what could cause insufficient heat if the warm air supply temperature is excessively high?

In a warm air heating system, if the warm air supply temperature is excessively high, it may lead to a situation where insufficient heat is felt in the space. This can occur when dirty air filters are present in the system. When air filters are clogged with dirt and debris, the airflow through the system is restricted. This restriction can prevent proper distribution of the heated air throughout the space, resulting in inadequate heating despite the high temperature of the air leaving the furnace. Essentially, the system may produce hot air, but if it cannot circulate effectively due to the obstructed filters, the environment will not receive the necessary warmth.

An additional factor is that restricted airflow can also lead to overheating of components within the heating system, potentially causing safety mechanisms to limit or shut down the operation. This makes routine maintenance, including changing or cleaning air filters, crucial for maintaining optimal performance and ensuring adequate heating.