What should temp be at vents?

The temperature at the vents of a well-functioning HVAC system should typically be between 15 to 20 degrees Fahrenheit lower than the indoor air temperature during cooling mode. For heating mode, vent temperatures can vary but should generally feel warm without being overly hot. It's important to regularly check and maintain your system to ensure optimal performance and comfort. If vent temperatures are significantly outside these ranges, it may indicate a need for service or maintenance.