My heat pump runs but will not get cold
I have a colmen furnace and heat pump
Frost fourms on the coils every time I turn on my air
Please help...

Turn off the AC unit and leave just the fan on, this will defrost the coil. When you turn on the AC does the blower come right on? Is the air cold? You could have several possibilities that are causing ice. Air flow through the coil, is the coil clean, is the fan running at the normal speed, is your filter clean? If all of these items are OK, your system could be low on refrigerant.