Goodman GMVC960803BN Error Code EE3: Open High Limit Switch

What Does Code EE3 Mean?

Error code EE3 on the Goodman GMVC960803BN indicates that the primary high limit switch circuit is open. This safety switch monitors the temperature inside the furnace and shuts off the burners when the heat exchanger gets too hot. The circulator blower will continue running to cool the furnace down.

The high limit switch trips when there is insufficient airflow across the heat exchanger. Without adequate air movement, heat builds up inside the furnace until it reaches the limit switch's threshold temperature. The switch opens the circuit and the control module stops the burners to prevent damage to the heat exchanger.

The most common cause is a clogged or dirty air filter that restricts return airflow. Blocked or closed supply and return vents, restrictive ductwork, an incorrect blower speed setting, or a failing circulator blower motor can also cause this condition. Loose wiring in the high limit circuit is another possibility.

Common Causes

How to Fix It: Replace the Air Filter and Restore Airflow

What You'll Need

• Replacement air filter (correct size for your system) 🛒 Find at FiltersFast · 🛒 Find at Amazon
• Flashlight

Steps

1. Turn off power at the breaker and shut off the gas supply valve Flip the furnace circuit breaker to OFF and turn the gas shutoff valve to the OFF position (perpendicular to the pipe). If you smell gas, leave your home immediately and call your gas company.
2. Check and replace the air filter Remove the air filter from the return air duct or the furnace filter slot. If it is visibly dirty or has not been changed in the last 1-3 months, replace it with a new filter of the correct size. Make sure the airflow direction arrow on the new filter points toward the furnace.
3. Verify all supply and return vents are open Walk through every room and check that all supply registers and return air grilles are fully open. Make sure none are blocked by furniture, rugs, curtains, or other objects. Even a few closed vents can significantly reduce airflow and cause overheating.
4. Inspect the blower area for debris With the power off, look into the blower compartment through the access panel opening. Check for excessive dust buildup on the blower wheel blades, which can reduce airflow. Also verify the blower wheel is securely attached to the motor shaft.
5. Restore power and gas, then test Turn the gas supply valve to ON and flip the circuit breaker to ON. Set your thermostat to call for heat and monitor the furnace through a full heating cycle. The high limit switch should reset automatically once the furnace cools down.

When to Call a Professional

Contact a licensed HVAC technician if:

• Code EE3 returns after replacing the filter and opening all vents
• The blower motor does not seem to be running at full speed or makes unusual noises
• The blower wheel is excessively dirty, loose, or damaged
• The problem recurs repeatedly even with a clean filter and open vents
• You suspect the high limit switch itself may be faulty

✓ Verified against manufacturer service manual — March 2026