,my Goodman package unit is blowing cold air, will not turn to Heat

SOURCE: Goodman HVAC Package Unit

Cycling the external switch on the GMS series will not help you. That switch is for A/C only. At the unit found inside the house, remove the front cover. If there is a door switch, tape it closed. Now if the thermostat is calling for heat, the unit will cycle as you mentioned. When the unit does not start, check for a blinking light on the circuit board. After three unsuccessful tries, the light will blink a code (2 blinks then a pause up to 9 blinks than a pause). Make a note of how many blinks you see. On the reverse side of the access panel you will find a diagnostic schematic. It should tell you a fault code corresponding with your blinking. This will give you a starting point where to look. If the codes are not found there, check inside your owner's manual. Or you can call Goodman at 713-861-250.
 
Get back to us with those codes and maybe we can help you further.

SOURCE: AIR or Heat wont come on/ goodman GMP075-3

If there is no blinking light, then the unit is not seeing a call for heat or cool. My guess is a lose or broken wire in the thermostat circuit. Try and putting a jumper across the red and white heat terminals inside the furnace and manually closing the door switch. If you get heat, it's telling you there is a wiring issue. If you get nothing, it's a bad circuit board.

SOURCE: my heat pump blows cold air for the first 10 minutes or so

Don't know how long you have had a heat pump but thats the nature of them in colder weather. Some people prefer to switch to "emergency heat" on the t-stat when temps fall below 20 or 25 degrees. This bypasses the heat pump and allows your back-up heat to heat the house. If your house is total electric your emergency heat is an electric furnace and it should handle the load if it was sized properly. Don't leave it on emergency when it warms up because your heat pump is much cheaper to operate than the furnace. As always, check your air filter since it can restrict the amount of air that moves thru the furnace, which is critical. Hope this helps

SOURCE: 1993 goodman status light 4 times blinking

I have a goodman GMP075-3 that won't turn on. I think it is the pressure switch since I do not have a vent blockage. What is a venter and where can I find it??