I have a question that might seem silly. I feel like maybe I should know this. Anyway, here goes. When I'm running the AC in my car on a hot humid day I always turn the blower motor on high so I can feel the cool air hitting me. But I notice that it doesn't seem to be as cold as it should until I turn the blower motor down to half or a little lower than that even? Is that normal? Its gets nice and cold, just seems that when the blower is on high, it doesn't feel as cold.
AC / Blower Motor function
- Thread starter Mark72
- Start date
- Status
The refrigeration system can not move more than a designed amount heat , under a specific set of conditions .
If the fan is blowing a small volume of air through the evaporator coil , the capacity of the refrigeration system is likely greater than needed . May cycle off and on .
It can drop the temperature quite a few degrees of temperature .
If the fan is moving its max amount of air , very likely the evaporator is " seeing " more BTU's of heat going through it . More than the capacity of the refrigeration system . Likely the refrigeration system will not cycle off & on . So , the temperature of the discharge air is greater than when the air flow is small .
If the fan is blowing a small volume of air through the evaporator coil , the capacity of the refrigeration system is likely greater than needed . May cycle off and on .
It can drop the temperature quite a few degrees of temperature .
If the fan is moving its max amount of air , very likely the evaporator is " seeing " more BTU's of heat going through it . More than the capacity of the refrigeration system . Likely the refrigeration system will not cycle off & on . So , the temperature of the discharge air is greater than when the air flow is small .
No expert here, but clearly the airflow being moved by the fan is greater than the capacity of the evaporator, compressor, and condenser to remove heat & humidity from it. It might be time to have someone check/re-charge your refrigerant.
Last edited:
It is normal. The higher the blower speed the higher rate of speed of the air passing through the evaporator coil. The air simply has less time to give up the heat to the coil. So the air is a bit warmer, but this is made up by the increased air volume circulating throughout the cabin as well as through the coil.
So you have slightly warmer air, but a lot more volume of it, so it cools the interior faster.
So you have slightly warmer air, but a lot more volume of it, so it cools the interior faster.
- Status
