Goodman gas furnace code EE3: Primary limit switch open

1. Not enough air across the heat exchanger because of blocked filters, restrictive ductwork, the wrong blower speed or a failed blower motor.

   Check and replace the furnace air filterYou can do this

   1. Turn off the electrical power to the furnace before you take the filter out.
      Never run the furnace without a filter in place.
   2. Find the filter. It sits outside the furnace cabinet, in a return air grille, a filter rack on the side of the furnace, or the duct next to it. If you cannot find or reach it, ask your installer.
   3. Replace a dirty disposable filter with one of the same size that meets UL900 or CAN/ULC-S111. Wash and dry a permanent filter the way its maker describes.
   4. Fit the filter so the air flows through it in the same direction as before, then turn the power back on.
   5. Check the filter at least once a month and clean or replace it when it is dirty. A dirty filter is the most common cause of a furnace not working properly.

   Clear blocked supply and return grillesYou can do this

   1. Go round the house and look at every supply register and return air grille.
   2. Move furniture, curtains, clothes, rugs or anything else that covers or blocks them.

   Book a licensed gas technician

2. Loose or wrongly connected wiring in the high limit circuit.

   Book a licensed gas technician

Booking a licensed gas technician